EPA 542-R-18-002
May 2018
http://www.epa.gov/remedytech
http://cluin.org
Examples of Groundwater
Remediation at NPL Sites
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Notice and Disclaimer
Preparation of this report has been funded by the U.S. Environmental Protection Agency (EPA) Office of
Superfund Remediation and Technology Innovation (OSRTI) under Contract Numbers EP-D-09-053 and
EP-W-14-001. Information in this report is derived primarily from EPA sources, including personal
communications with EPA staff familiar with the remedies discussed in this report. Some information was
also obtained from state personnel and remediation contractors. This report is not intended, nor can it be
relied upon, to create any rights enforceable by any party in litigation with the United States. Mention of
trade names or commercial products does not constitute endorsement or recommendation for use.
A PDF version of Examples of Groundwater Remediation at NPL Sites is available for viewing or
downloading from https://www.epa.gov/remedvtech, or http://www.cluin.org. For questions concerning this
document, contact Linda Fiedler at fiedler.linda@epa.gov or 703-603-7194.
Acknowledgements
Acknowledgment is given to the federal and state Remedial Project Managers and technical staff and other
remediation professionals for providing information for this document. Their cooperation and willingness to
share their expertise on Superfund remedies will help regulators and system operators make informed
decisions that will promote progress towards remedial action objectives at NPL and other contaminated sites
throughout the U.S. and other nations.
Cover pictures from top, clockwise: Groundwater treatment facility at Pemaco Superfund Site; In situ thermal
treatment at Fort Lewis Logistics Center Superfund Site; Treatment Plant #1 at Holingsworth Solderless
Terminal Superfund Site; Treatment building and air stripper tower at Tabernacle Drum Dump Superfund
Site.
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Table of Contents
Notice and Disclaimer i
Acknowledgements i
List of Tables iv
List of Figures iv
List of Acronyms and Abbreviations v
Executive Summary vii
1. Purpose and Scope 1
1.1 Remedial Action Objectives and Associated Cleanup Levels 1
1.2 Site Selection Process 2
2. Observations and Analysis of Cleanups 3
2.1 Technologies Applied to Restore Groundwater 7
2.2 Technologies Used at DNAPL Sites 11
2.3 Cleanup Magnitude 12
2.4 Cleanup Time 14
3. Sites Returned to Use 17
3.1 Industrial/Commercial Reuse 17
3.2 Recreational Use 17
3.3 Alternative Energy Development 17
3.4 Other Reuses 18
4. Conclusions 19
Appendix A: Site Information Summary Tables A-1
Appendix B: Case Summaries B-1
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List of Tables
Table 2.1 NPL Sites that Achieved Groundwater Restoration 3
Table 2.2 NPL Sites that Achieved Significant Progress towards Groundwater Restoration 4
Table 2.3 Hydrogeologic Setting and Contaminant Phase 6
Table 2.4 Remedial Technologies Applied at DNAPL Sites 11
Table 3.1 Sites Returned to Use 18
Table A.1 Location, Industry Type, Contaminant Group, and Remedial Technology for NPL
Sites that Achieved Groundwater Restoration A-1
Table A.2 Location, Industry Type, Contaminant Group, and Remedial Technology for NPL
Sites that Achieved Significant Progress towards Groundwater Restoration A-2
Table A.3 Summary of Technologies Applied to Restore Groundwater A-3
Table A.4 Time to Meet RAOs and Hydogeologic Complexity for Sites that Achieved
Groundwater Restoration A-6
Table A.5 Time to Achieve Significant Progress and Complexity for Selected Sites that
Achieved Significant Progress towards Groundwater Restoration A-9
Table A.6 Site Information Summary Table A-10
List of Figures
Figure 2.1 Frequency of Contaminant Classes at 30 NPL Sites 5
Figure 2.2 Remedial Technologies and Approaches Associated with 30 NPL Sites 7
Figure 2.3 Remediation Timeline for Gold Coast Oil Corporation 8
Figure 2.4 Number of Technologies used to Achieve Groundwater Restoration 9
Figure 2.5 Number of Technologies at Sites that Achieved Significant Progress towards
Groundwater Restoration 10
Figure 2.6 Remediation Timeline for Southern California Edison Co., Visalia Pole Yard 12
Figure 2.7 Magnitude of Contaminant Concentration Decreases at Sites that Achieved
Groundwater Restoration 13
Figure 2.8 Magnitude of Contaminant Concentration Decreases at Sites that Achieved
Significant Progress towards Groundwater Restoration 14
Figure 2.9 Cleanup Time and Magnitude for Sites that Achieved Groundwater Restoration 16
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List of Acronyms and Abbreviations
Bgs below ground surface
CERCLA Comprehensive Environmental
Response, Compensation and
Liability Act
COC Contaminant of Concern
DCE dichloroethene
DNAPL Dense Non-aqueous Phase
Liquid
DUS Dynamic Underground Stripping
EPA U.S. Environmental Protection
Agency
ERD Enhanced Reductive
Dechlorination
ERH Electrical Resistance Heating
ESD Explanation of Significant
Differences
ISCO In Situ Chemical Oxidation
ISCR In Situ Chemical Reduction
ISTT In Situ Thermal Treatment
LNAPL Light Non-aqueous Phase Liquid
MCL Maximum Contaminant Level
MNA Monitored Natural Attenuation
NCP National Oil and Hazardous
Substances Pollution
Contingency Plan
NPL National Priorities List
OSRTI Office of Superfund Remediation
and Technology Innovation
OU Operable Unit
PAH Polycyclic Aromatic Hydrocarbon
PCB Polychlorinated Biphenyl
PCE Tetrachlorothene
ppm Parts per million
RAO Remedial Action Objective
RCRA Resource Conservation and
Recovery Act
ROD Record of Decision
RPM Remedial Project Manager
SVE Soil Vapor Extraction
SVOC Semivolatile Organic Compound
SWRAU Sitewide Ready for Anticipated
Use
TCE trichloroethene
TSD Treatment, Storage and Disposal
UST Underground Storage Tank
UXO Unexploded Ordnance
VEB Vertical Engineered Barrier
VOC Volatile Organic Compound
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vi
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Executive Summary
Executive Summary
This report documents where innovative and established technologies have been used to restore
groundwater to beneficial use. This report includes a select number of example National Priorities
List (NPL) sites where the remedial action objective (RAO) and associated cleanup levels were to
restore groundwater for use as a source of drinking water. Groundwater was restored for use as
drinking water at 17 NPL sites and significant progress toward groundwater restoration has been
made at an additional 13 NPL sites where contaminants remain above safe drinking water levels in
only a few groundwater wells. The RAO of restoring groundwater for beneficial use was achieved
under the Superfund program, including the successful treatment of groundwater to federal and state
maximum contaminant levels for drinking water. These sites are examples of where the Superfund
program overcame difficult remediation challenges, such as groundwater contaminated with
chlorinated solvents (including the presence of dense non-aqueous phase liquids [DNAPLs]) and
complex hydrogeologic settings.
The NPL sites discussed in this report were selected based on several criteria, including the use of
innovative cleanup technologies or approaches to remedy concentrated groundwater plumes. The
most commonly occurring contaminants of concern at these sites were chlorinated volatile organic
compounds, which were present at 26 of the 30 sites. The less frequently occurring contaminants
included metals, non-chlorinated volatile organic compounds, semivolatile organic compounds,
polychlorinated biphenyls, and polycyclic aromatic hydrocarbons, with dioxins or pesticides only
present at one site.
The restoration of groundwater was achieved most often by combining remedial technologies. For
example, soil excavation and groundwater extraction and treatment (i.e., pump-and-treat) were used
to restore groundwater at 17 of the 30 NPL sites. Given that many of these sites were cleaned up
during the period from 1983 to 2000, the remedies used at these sites represented state of the art
technologies at that time. These traditional technologies were often modified or replaced with
innovative technologies such as in situ bioremediation, in situ chemical oxidation (ISCO), in situ
thermal treatment (ISTT) or monitored natural attenuation (MNA) at some sites. The application of
remedial technologies at these sites decreased contaminant concentrations from 90% up to 99.99%
(i.e., one to more than four orders of magnitude).
DNAPLs were found or suspected at eight of the 30 sites. A combination of excavation and pump-
and-treat was used most often to remediate these sites along with at least one other technology or
approach such as vertical engineered barrier, air sparging, in situ bioremediation, ISTT, or MNA. Of
the eight DNAPL sites, groundwater was restored for use as drinking water at three sites and
significant progress towards restoration has been made at five sites. These findings indicate that the
Superfund program has achieved the cleanup of sites with DNAPLs.
The time required to restore groundwater for use as drinking water at the 17 NPL sites ranged from
three to 27 years with a median time of eight years. Cleanup time generally increased as the amount
of contaminant removed increased with the exception of four sites where contaminant
concentrations were decreased by nearly 99.99% in less than eight years. Cleanup times were
generally shorter for sites with less complex hydrogeologic settings with the exception of three sites
with mild heterogeneity that required more than 15 years to restore groundwater. Also, in most
cases, cleanup times were shorter for lesser reductions in concentration.
All of the 30 sites, with the exception of two, have achieved the status of sitewide ready for
anticipated reuse (SWRAU), and 12 of these sites have been returned to use either in whole or in
part. Reuse includes industrial and commercial redevelopment, recreational use, alternative energy
use, and lifting of groundwater use restrictions.
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Purpose and Scope
1. Purpose and Scope
The report is intended for federal and state agency personnel, potentially responsible parties,
cleanup consultants, and remediation site managers to demonstrate where innovative and
established technologies have been used to restore groundwater to beneficial use. As such, this
report documents a select number of example NPL sites where the remedial action objective (RAO)
and associated cleanup levels were to restore groundwater for use as a source of drinking water.
Cleanups that only addressed contaminated soils are not included. However, soil cleanup is covered
where it was part of the effort to restore groundwater.
The NPL sites in this report contained contaminants of concern (COCs) such as chlorinated and
non-chlorinated volatile and semivolatile organic compounds (VOCs and SVOCs), polycyclic
aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pesticides, and metals. This
report excludes sites that were primarily contaminated with petroleum hydrocarbons, contained
unexploded ordnance (UXO) or radioactive contamination.
Groundwater contamination at these sites resulted from operations including landfills or dumps,
chemical production, manufacturing, metal works or plating, waste storage and disposal, and wood
treatment facilities. The sites are in residential neighborhoods, industrial parks or former factories,
and at federal facilities.
This report is not intended to be a remedial technology primer and does not contain general
descriptions of the technologies applied. More information about the breadth of technologies,
contaminant groups, and remedies is addressed in other documents such as the Superfund Remedy
Report, Fifteenth Edition1 and the Contaminated Site Clean-Up Information (CLU-IN ) website.
1.1 Remedial Action Objectives and Associated Cleanup Levels
Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) RAOs specify
"contaminants and media of concern, potential exposure pathways, and remedial goals."3 Consistent
with the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), "RAOs provide
a general description of what the cleanup will accomplish (e.g., restoration of groundwater to
drinking water levels)."4 Groundwater remedies will often have a restoration RAO based on the NCP
expectation that groundwater will be restored to its beneficial use within a reasonable timeframe.5
Drinking water is most often the beneficial use of groundwater, but non-potable use is possible if
groundwater is determined to be unsuitable for human consumption6. Sites with multiple types of
contaminated media, unusual media, or a very large extent of contamination are often addressed
with multiple types of RAOs.
1 http://www.clu-in.org/asr/
2 http://www.clu-in.org/
3 40 CFR 300.430(e)(2)®
4EPA. 1999a. A Guide to Preparing Superfund Proposed Plans. Records of Decision and Other Remedy
Selection Decision Documents. OSWER Directive No. 9200.1-23P.
5 "EPA expects to return usable ground waters to their beneficial uses wherever practicable, within a time
frame that is reasonable given the particular circumstances of the site. When restoration of ground water
to beneficial uses is not practicable, EPA expects to prevent further migration of the plume, prevent
exposure to the contaminated ground water, and evaluate further risk reduction" 40 CFR
300.430(a)(1)(iii)(F).
6 Groundwater Use Policy (55 FRN 8732)
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Purpose and Scope
RAOs may include specific cleanup levels for the media and the objective addressed.7 Examples of
cleanup levels include maximum contaminant levels (MCLs), which are drinking water standards
established under the Safe Drinking Water Act. Federal MCLs are often Applicable or Relevant and
Appropriate Requirements (ARARs) for groundwater remedies at NPL sites. The RAOs for each of
the 30 NPL sites included in this report are presented in Table A.6. This report does not assess
every cleanup RAO and associated cleanup level for all of the NPL sites presented. For example,
the report does not discuss some RAOs and cleanup levels for soil if they are not related to the
groundwater cleanup. In order to simplify the discussion of remedy performance, the report only
includes cleanup levels for a subset of contaminants of concern, for instance those with the highest
initial concentrations or that are representative of the cleanup progress.
1.2 Site Selection Process
To determine which sites to include in this report, the following information sources were reviewed:
• List of sites deleted from the NPL.
• Recommendations from EPA, state, and other federal Remedial Project Managers (RPMs),
EPA regional technical staff and headquarters staff.
• Databases accessed through online sources such as Federal Remediation Technologies
Roundtable8 (FRTR), Interstate Technology & Regulatory Council9 (ITRC), and CLU-IN.
• EPA Superfund site profile websites and fact sheets.
Out of this review approximately 175 sites were identified as candidates for inclusion in this report.
From these, the final sites were selected based on one or more of the following criteria:
• Achieved groundwater restoration.
• Groundwater plume with initial contaminant concentrations of greater than 100 micrograms
per liter (|jg/L or ppb).
• Utilized innovative cleanup technologies or approaches.
• Site was redeveloped or ready for reuse and redevelopment.
In addition, an attempt was made to represent a range of contaminant types, remedies used, and
hydrogeologic complexity. Sites with an ongoing cleanup were included if they fit the above criteria
and where contaminants remain above cleanup levels in only a few groundwater wells. These sites
have achieved significant progress towards groundwater restoration.
7 40 CFR 300.430(e)(2)®
8 https://frtr.gov/
9 http://www.itrcweb.org/
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Observations and Analysis
2. Observations and Analysis of Cleanups
This report addresses groundwater remedies at 30 NPL sites, including 17 remedies that have achieved
groundwater restoration (Table 2.1) and 13 that have achieved significant progress towards groundwater
restoration (Table 2.2). The cleanups that achieved groundwater restoration were listed on the NPL
between 1983 and 1990, and all but two were deleted from the NPL between 1996 and 2011 with a total
time listed on the NPL ranging from 11 to 25 years (Table 2.1).
Table 2.1 NPL Sites that Achieved Groundwater Restoration
Site
Year
Listed
Years on
NPL
Cleanup
Levels
1. Del Norte County Pesticide Storage, CA (OU 1)
1984
18
Fed MCLf
2. Firestone Tire and Rubber, CA (OU 1)
1987
18
State MCL/
Risk Based
3. Frontier Hard Chrome, Inc., WA (OU's 1 and 2)
1983
*
Fed MCL/
State MCL
4. Gold Coast Oil Corp., FL (OU 1)
1983
13
Fed MCL
5. Island Chemical Corp/V.l. Chemical Corp, Virgin Islands (OU 1)
1996
13
Fed MCL
6. Mannheim Avenue Dump, NJ (OU 1)
1983
24
State MCL
7. Odessa Chromium II, TX (OU's 1-3)
1986
18
Fed MCL
8. Pasley Solvents and Chemicals, Inc., NY (OU 1)
1986
25
Fed MCL
9. Rochester Property, SC (OU 1)
1989
18
Fed MCL
10. SMS Instruments, NY (OU 1)
1986
24
Fed MCL/
State MCL
11. Southern California Edison, Visalia Pole Yard, CA (OU 1)
1989
20
Fed MCL*
12. Tabernacle Drum Dump, NJ (OU 1)
1984
24
State MCL
13. Tri-State Plating, IN (OU 1)
1986
11
Fed MCL
14. Vestal Water Supply Well 4-2, NY (OU 1)
1983
16
Fed MCL
15. Waverly Groundwater Contamination, NE (OU 1)
1986
20
Fed MCL
16. Western Pacific Railroad Co., CA (OU 1)
1990
11
Fed MCL/
Sate MCL
17. Western Processing, WA (OU 2), Offsite Trans Plume
1983
**
Fed MCL
Notes:
technical Impracticability (Tl) waiver for MCL in 2002, EPA plans to amend Tl waiver to allow for unrestricted use.
* Deletion anticipated in 2018, pending review of all criteria.
Covenant between Southern California Edison and the California Department of Toxics Substance Control (DTSC) prohibits
installation of water wells for any purpose.
** Offsite trans plume achieved RAOs, however, other OUs at Western Processing still undergoing cleanup; therefore, the
site remains on the NPL.
The sites where contaminants remain above cleanup levels in only a few wells were listed on the NPL
between 1983 and 1996 (Table 2.2).
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Observations and Analysis
Table 2.2 NPL Sites that Achieved Significant Progress towards Groundwater Restoration
Site
Year
Listed
Cleanup Levels
1. Browns Battery Breaking, PA (OU's 1 and 2)
1986
Fed MCL/ State MCL
2. Dover AFB - SS07/Area 2, DE (OU 15)
1989
State MCL
3. Eastern Surplus Company, ME
1996
Fed MCL
4. Fort Lewis Logistics Center, WA (East Gate Disposal Yard, Landfill 2)
1989
Fed MCL
5. Hollingsworth Solderless Terminal, FL (OU 1)
1983
Fed MCL
6. King of Prussia, NJ (OU's 1-3)
1983
Risk Based/ Fed MCL
7. LeHillier/Mankato Site, MN (OU 1)
1983
Fed MCL
8. Letterkenny Army Depot (Southeast Area), PA (OU 10)
1987
Fed MCL
9. Malvern TCE, PA (OU's 1-4)
1983
Fed MCL
10. Mystery Bridge Road/Highway 20 (Dow/DSI), WY (OU's 1 and 2)
1990
Fed MCL
11. NCR Corp., DE (OU 1)
1987
Fed MCL
12. Pemaco, CA(OU 1)
1999
Fed MCL
13. US Aviex, Ml (OU 1)
1983
Risk Based/ Fed MCL
The cleanup levels for sites with multiple contaminants can be based on federal MCLs for one contaminant
and state MCLs for another. Some contaminants have cleanup levels based on equivalent federal and
state MCLs. Four cleanups achieved a state-based MCL that was more stringent than the federal MCL,
including:
• Firestone Tire and Rubber site in California where 1,1-dichloroethene (1,1 -DCE) was reduced from
a maximum of 120 ppb to less than the California cleanup level of 6 ppb (Federal MCL of 70 ppb).
• Mannheim Avenue Dump site in New Jersey where trichloroethene (TCE) was reduced from a
maximum of 140 ppb to less than the New Jersey cleanup level of 1 ppb (Federal MCL of 5 ppb).
• Tabernacle Drum Dump site in New Jersey where trichloroethane (TCA) was reduced from a
maximum of 1,000 ppb to less than the New Jersey cleanup level of 26 ppb (Federal MCL of 200
ppb).
• SMS Instruments site in New York where total dichlorobenzene was reduced from a maximum of
570 ppb to below the New York cleanup level of 3 ppb (Federal MCLs of 600 ppb for o-
dichlorobenzene and 75 ppb for p-dichlorobenzene).
The most commonly occurring COCs were chlorinated VOCs, which were present at 26 of the 30 sites
(Figure 2.1). Metals were also prevalent, and were COCs at 12 of the 30 sites. The less frequently
occurring contaminants included non-chlorinated VOCs, SVOCs, and PCBs.
The presence of DNAPL was observed as a separate phase in groundwater monitoring wells or
groundwater samples at two sites including:
• Fort Lewis Logistics Center, WA (East Gate Disposal Yard, Landfill 2)
• Southern California Edison, Visalia Pole Yard (OU 1)
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Observations and Analysis
Figure 2.1 Frequency of Contaminant Classes at 30 NPL Sites
30
Contaminant Class
DNAPL was suspected to be present based on contaminant concentrations being above one percent of
their aqueous solubility limit10 at the following sites:
• Dover AFB - SS07/Area 2 (OU 15)
• Gold Coast Oil Corp. (OU 1)
• Malvern TCE (Oil's 1-4)
• Pasley Solvents and Chemicals, Inc. (OU 1)
• NCR Corp. (OU 1)
• Pemaco(OUI)
The groundwater restoration remedies presented in this report were implemented at sites that represent a
wide range of hydrogeologic environments. As shown in Table 2.3, the sites have been categorized into
one of four different hydrogeologic settings, from granular media (e.g., sand) with mild to high
heterogeneity (Types I and III) to more heterogeneous fractured media (Types IV and V). These
hydrogeologic settings correspond to how contaminants are stored and released in the subsurface where
regions with higher storage potential generally equate to longer cleanup times11.
10 USEPA. Estimating Potential for Occurrence of DNAPL at Superfund Sites. OSWER Publication 9355.4-
07FS. January 1992.
11 Contaminants in the Subsurface: Source Zone Assessment and Remediation, Committee on Source Removal
of Contaminants in the Subsurface, National Research Council, 2004 (http://www.nap.edu/cataloq/11146.html).
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Observations and Analysis
Table 2.3 Hydrogeologic Setting and Contaminant Phase
Hydrogeologic
Setting
Contaminant Phase
Dissolved Phase
DNAPL or Suspected
DNAPL
Granular Media with
Mild Heterogeneity
(Type I)
• Del Norte County Pesticide Storage, CA (OU 1)
• Hollingsworth Solderless Terminal, FL (OU 1)
• LeHillier/Mankato Site, MN (OU 1)
• SMS Instruments, NY (OU 1)
• Tabernacle Drum Dump, NJ (OU 1)
• Tri-State Plating, NJ (OU 1)
• Waverly Groundwater Contamination, NE (OU 1)
• Gold Coast Oil Corp., FL (OU 1)
• Pasley Solvents and Chemicals,
NY (OU 1)
Granular Media with
Moderate to High
Heterogeneity (Type
III)
• Browns Battery Breaking, PA (OU's 1 and 2)
• Eastern Surplus Company, ME (OU 1), Southern
PCE Plume
• Firestone Tire and Rubber, CA (OU 1)
• Frontier Hard Chrome, Inc., WA (OU's 1-2)
• Island Chemical Corp/V.l. Chemical Corp, Virgin
Islands (OU 1)
• King of Prussia, NJ (OU's 1-3)
• Mannheim Avenue Dump, NJ (OU 1)
• Mystery Bridge Road/Highway 20 (Dow/DSI), WY
(OU's 1 and 2)
• US Aviex, Ml (OU 1)
• Vestal Water Supply Well 4-2, NY (OU 1)
• Western Pacific Railroad Co., CA (OU 1)
• Western Processing, WA (OU 2, Offsite Trans
Plume
• Dover AFB, SS07/Area 2, South
Management Unit (OU 15)
• Fort Lewis Logistics Center, WA
- East Gate Disposal Yard
(Landfill 2)
• Pemaco, CA (OU 1)
• NCR Corp. (OU 1)
• Southern California Edison,
Visalia Pole Yard, CA (OU 1)
Fractured Media with
Low Matrix Porosity
(Type IV)
• Malvern TCE (OU's 1-4)
Fractured Media with
High Matrix Porosity
(Type V)
• Letterkenny Army Depot (Southeast Area), PA
(OU 10)
• Odessa Chromium II, TX (OU's 1-3)
• Rochester Property, SC (OU 1)
None
Notes:
(1) None of the sites in this report had hydrogeology described as granular media with mild heterogeneity and low permeability (Type II).
(2) LNAPL also present at Fort Lewis East Gate Disposal Yard.
The following sections discuss the technologies applied to restore contaminated groundwater (2.1), the
technologies used at sites where DNAPL was observed or suspected (2.2), the decrease in contaminant
levels achieved by the cleanup (2.3), and the time required to accomplish the cleanup (2.4). Appendix A
contains several tables summarizing the detailed site information which served as the basis for the
following sections. Appendix B contains case summaries for 17 of the 30 NPL sites. These case
summaries include a brief description and history of the site, the extent of contamination, the remedial
technologies used, and the successes achieved. This information was gathered from site-specific
documents such as Five-Year Reviews, Record of Decisions (RODs), ROD Amendments, Explanations
of Significant Differences, Remedial Investigation Reports, Feasibility Studies, Remedial and Removal
Action Reports and Long Term Monitoring Reports.
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Observations and Analysis
2.1 Technologies Applied to Restore Groundwater
Figure 2.2 shows the number of times a technology was used at a NPL site and is based on the summary
tables presented in Appendix A (Table A.1 and Table A.2). The technologies applied to restore
groundwater at the 30 NPL sites fit into 12 categories as summarized in Figure 2.2. The categorization of
technologies was done for the sake of this analysis and contains some assumptions. For example,
hydrogen peroxide was injected while operating a pump-and-treat system at some sites and this was
categorized as pump-and-treat rather than as in situ chemical oxidation (ISCO) and pump-and-treat. This
was because the hydrogen peroxide was added to improve contaminant recovery by degrading organic
carbon rather than degrading the contaminant of concern. The category excavation/removal includes both
the excavation of soil and removal of drums or debris. Some of these technologies only addressed
contaminated groundwater (e.g., pump-and-treat), others were used to remove contaminants only from soil
(e.g., soil vapor extraction or SVE), while some were used to remove contaminants from groundwater and
soil (e.g., in situ thermal treatment). Given that contaminated soil can serve as the long-term source of
groundwater contamination, this report includes all the technologies that were applied at a given site to
restore groundwater, even if the technology only addressed contaminated soil.
Figure 2.2 Remedial Technologies and Approaches Associated with 30 NPL Sites
Number of Applications
0 5 10 15 20 25
Pump-and-Treat
Excavation/Removal
SVE
MNA
g; Air sparging
O
c In Situ Bioremediation
£
h Cap
ISCR
ISCO
ISTT
VEB
In Situ pH Adjustment
Figure 2.2 shows that pump-and-treat and excavation/removal were the most commonly applied
technologies at the 30 NPL sites. Some sites had more than one pump-and-treat system, but were counted
as only one application for this report. Other technologies implemented at sites with groundwater cleanups
included SVE, monitored natural attenuation (MNA), capping, air sparging, in situ bioremediation, ISCO, in
situ chemical reduction (ISCR), in situ thermal treatment (ISTT), and in situ pH adjustment. Vertical
engineered barriers (VEB) were used to temporarily contain contaminated groundwater at two sites as part
of groundwater restoration efforts.
The four ISCO applications used ozone, sodium permanganate or hydrogen peroxide to remediate
chlorinated VOCs. Among the three ISTT applications, electrical resistance heating (ERH) was used at two
sites, and dynamic underground stripping (DUS) with steam (a form of ISTT similar to steam enhanced
extraction) was used at one site. Two of the ISCR applications were conducted to remediate hexavalent
Achieved Groundwater Restoration
Achieved Significant Progress
towards Groundwater Restoration
7
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Observations and Analysis
chrome (Cr6+) contamination. At both sites Cr6+ was reduced to Cr3+ using sodium dithionite or ferrous
sulfate as the reducing agent.
Figure 2.2 shows the total number of technologies used
to restore groundwater at the 30 NPL sites. When
viewed from a site-specific perspective, multiple
technologies were used in combination to restore
groundwater. For example, at the Gold Coast Oil Corp.
site, excavation was initially used to remove soil
contaminated with VOCs, followed by four years of
pump-and-treat (P&T), and finally excavation and air
sparging were used to remove regions suspected to
contain DNAPL (Figure 2.3). Thus, three technologies
(excavation, pump-and-treat, and air sparging) were
used to restore groundwater at the Gold Coast Oil Corp.
site in a period of six years (1989 to 1995).
Figure 2.4 shows that the number of technologies used
at the sites that achieved groundwater restoration
ranged from one to as many as six, and was most
commonly the combination of two or three technologies.
Importantly, Figure 2.4 is not a timeline indicating the
order in which these technologies were used at a site.
The most frequently used technology combination was
excavation/removal and pump-and-treat, which was
used at 10 of the 17 sites. Given that many of these
sites were cleaned up during the period from 1983 to
2000, these remedies represented state of the art
technologies at that time.
Figure 2.3 Remediation Timeline for Gold Coast Oil Corporation
Gold Coast Oil Corporation Superfurid Site:
Achieved Groundwater Restoration in Six Years
The Gold Coast Oil Corp. Superfund site is a 2-
acre property that operated as an oil and solvent
reclamation and bulk storage facility from the early
1970s until 1982. Remedial actions included the
excavation and disposal of visibly contaminated
soil in 1989, followed by extracting groundwater
from five wells and treating with air stripping towers
beginning in 1990, There were two efforts to
enhance contaminant extraction during pump-and-
treat operation, first hydrogen peroxide was
injected into two monitoring wells that were located
in an area suspected to contain DNAPL. Second,
the groundwater extraction system was shut down
periodically. The pump-and-treat system was
permanently shut down in 1994 and additional soil
excavation and air sparging of groundwater
(without pump-and-treat) in two areas of suspected
DNAPL were subsequently performed in 1995. This
approach reduced groundwater concentrations to
below federal, state, and county cleanup levels.
Overall, the RAOs and cleanup levels were
achieved in approximately six years. The site was
deleted from the NPL in October 1996.
P&T Start
Excavation
P&T Shutdown
Air Sparging
1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996
NPL Listing
ROD
Excavation
NPL Deletion
DNAPL Excavation
8
-------
Observations and Analysis
Figure 2.4 Number of Technologies used to Achieve Groundwater Restoration
Del Norte County Pesticide Storage, CA (OU 1
Firestone Tire and Rubber, CA (OU 1
Frontier Hard Chrome, WA (OU's 1 and 2
Gold Coast Oil Corp., FL (OU 1
Island Chemical Corp, Virgin Islands (OU 1
Mannheim Avenue Dump, NJ (OU 1
Odessa Chromium II, TX (OU's 1-3
Pasley Solvents and Chemicals, NY (OU 1
Rochester Property, SC (OU 1
SMS Instruments, NY (OU 1
Visalia Pole Yard, CA (OU 1
Tabernacle Drum Dump, NJ (OU 1
Tri-State Plating, IN (OU 1
Vestal Water Supply Well 4-2, NY (OU 1
Waverly Groundwater Contamination, NE (OU 1
Western Pacific Railroad, CA (OU 1
Western Processing, WA (OU 2} Offsite Trans Plume
Air Sparging >Cap
¦ ISCO E ISCR
¦ Pump-and-Treat SVE
Number of Technologies Used
2 3 4
Y/////A
KDNAPL (observed or suspected)
¦ Excavation/Removal
WISTT
¦ VEB
I In Situ Bioremediation
l MIMA
While traditional technologies such as pump-and-treat and air sparging were able to achieve groundwater
restoration at some sites (e.g., Gold Coast, Firestone Tire and Rubber, Tabernacle Drum Dump, Tri-State
Plating), there are examples of where these technologies were modified or replaced in an effort to meet
cleanup levels. As detailed in Table A.3, the air sparging system at the Rochester Property was modified to
include ozone to address increasing TCE concentrations. At the Mannheim Avenue Drum Dump site, after
18 months of operating a pump-and-treat system, influent TCE concentrations had decreased to less than
1 ppb. However, after the pump-and-treat system was shut down, TCE concentrations in two of the 32
monitoring wells remained above the New Jersey cleanup level of 1 ppb. Thereafter, MNA was employed
for six years to achieve the cleanup level of 1 ppb in all monitoring wells.
9
-------
Observations and Analysis
Figure 2.5 Number of Technologies at Sites that Achieved Significant Progress towards
Groundwater Restoration
Number of Technologies Used
2 3 4
*DNAPL (observed or suspected)
0 1
Browns Battery Breaking, PA (OU's 1 and 2)
Dover Air Force Base (AFB), SS07/Area 2, DE
Eastern Surplus Company, ME (OU 1)
East Gate Disposal Yard, WA (Landfill 2)
Hollingsworth Solderless Terminal, FL(OU 1)
King of Prussia, NJ (OU's 1-3)
LeHillier/Mankato Site, MN (OU 1)
Letterkenny Army Depot (Southeast Area), PA (OU 10)
Malvern TCE, PA (OU's 1-4) mm
Mystery Bridge Road (Dow), WY (OU's 1 and 2)
NCR Corp., DE (OU 1)
Pemaco, CA (OU 1)
US Aviex, Ml (OU 1)
AirSparging ">Cap ¦ Excavation/Removal ¦ In Situ Bioremediation
¦ I n Situ pH ¦ ISCO = ISCR 2JISTT
¦ MNA ¦ Pump-and-Treat SVE
The combination of excavation/removal and pump-and-treat was also used frequently at the sites that
achieved significant progress towards groundwater restoration (Figure 2.5). However, compared to the
sites that achieved groundwater restoration (Figure 2.4), the combination of five technologies was the most
frequent indicating these sites used additional technologies. For example, at Hollingsworth Solderless, it
was determined that a pump-and-treat system was no longer effective at decreasing concentrations of
TCE, c/s-1,2-DCE and vinyl chloride after two years of operation (Table A.3). After a successful pilot test of
in situ bioremediation, a ROD Amendment was issued in 2008 modifying the site remedy from pump-and-
treat to in situ bioremediation (i.e., enhanced reductive dechlorination). As of 2016, only four out of the 24
wells being monitored exceed the State of Florida standard of 1 ppb for vinyl chloride.
Sufficient information was available in the case studies presented in Appendix B to identify 11 groundwater
restoration remedies that were changed or optimized after the initial remedies specified in the decision
document were implemented. The remedy changes described in Table A.3 include those where a
groundwater restoration remedy technology or approach was changed after implementation, or a formal
optimization review was conducted, such as an EPA Remediation System Evaluation (RSE)
12
' 'For more information on RSEs at Superfund sites, see Cleanup Optimization at Superfund Sites.
10
-------
Observations and Analysis
2.2 Technologies Used at DNAPL Sites
Groundwater restoration was achieved at three sites where DNAPL was observed or suspected (Gold
Coast Oil Corp., Pasley Solvents and Chemicals, and Southern California Edison Visalia Pole Yard) (Table
2.4). Significant progress toward groundwater restoration was achieved at five sites where DNAPL was
observed or suspected (Dover AFB - SS07/Area 2, Fort Lewis Logistics Center [Landfill 2], Malvern TCE,
NCR Corp., and Pemaco). Excavation/removal and pump-and-treat were the technologies most often used
at these sites, followed by SVE, in situ bioremediation, air stripping, MNA, ISTT, with one application of
capping, VEB, or ISCR.
Table 2.4 Remedial Technologies Applied at DNAPL Sites
Site
DNAPL
Remedial Technologies Applied
Remedy Achieved
Excavation/Removal
Pump-and-Treat
Capping
SVE/MPE
In Situ Bioremediation
Air Sparging
VNIAI
VEB
ISCR
In Situ Thermal Treatment
Gold Coast Oil Corp., FL
Suspected
•
•
•
Unrestricted Use/
Pasley Solvents and Chemicals, Inc.,
NY
Suspected
•
•
Unrestricted Exposure
Southern California Edison, Visalia
Pole Yard, CA
Observed
•
•
•
•
•
•
MCLs*
Dover AFB - SS07/Area 2, DE
Suspected
•
•
Fort Lewis Logistics Center, WA
(East Gate Disposal Yard, Landfill 2)
Observed
•
•
•
Malvern TCE, PA
Suspected
•
•
•
•
•
Significant Progress
NCR Corp., DE
Suspected
•
•
•
•
•
Pemaco, CA
Suspected
•
•
•
•
•
Total
5
5
1
4
4
4
3
1
1
3
Note: Covenant between Southern California Edison and California Department of Toxics Substance Control (DTSC)
prohibits installation of water wells for any purpose.
At the Visalia Pole Yard, pools of DNAPL were observed at the bottom of the shallow and intermediate
aquifers. As shown in the timeline in Figure 2.6, a number of technologies were used to restore these
aquifers. Initial efforts involved installing a VEB to slow the lateral migration of contaminants in the shallow
aquifer and excavating contaminated soil. This was followed by the installation of a pump-and-treat (P&T)
system which operated for 15 years. While the P&T system was operating, an ISTT system (DUS) was
employed followed by biosparging. Overall, approximately 1.33 million pounds of contaminants were
removed using the combination of technologies shown in Figure 2.6. Although groundwater contaminant
concentrations at the Visalia Pole Yard were reduced to below MCLs, Southern California Edison and the
California Department of Toxic Substances Control signed a covenant which prohibits the installation of
water wells for any purpose.
11
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Observations and Analysis
Figure 2.6 Remediation Timeline for Southern California Edison Co., Visalia Pole Yard
P&T Start P&T Shutdown
VEB Excavation DUS Start
DUS Shutdown Excavation
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Biosparging
NPL Listing ROD NPL Deletion
2.3 Cleanup Magnitude
One measure of cleanup is based on comparing the maximum contaminant concentration before cleanup
to the maximum concentration after cleanup. For example, at the Gold Coast Oil Corp. Superfund site, the
maximum concentration of tetrachloroethene (PCE) in groundwater prior to remediation was 100,000 ppb
whereas after applying excavation/removal, pump-and-treat and air sparging, PCE concentrations were
below the federal MCL of 5 ppb, which represents a decrease in PCE concentration of greater than 20,000
times. This indicates that the PCE concentration at the Gold Coast Oil Corp. site decreased by greater
than four orders of magnitude (i.e., base 10 logarithm of 20,000 is 4.3). Figure 2.7 shows the magnitude of
contaminant decreases for the 17 sites that achieved groundwater restoration, which ranged from just over
one order at Firestone Tire and Rubber to more than four orders at the Island Chemical Corp. and Gold
Coast Oil Corp. The remedies that demonstrated the greatest contaminant concentration decreases
included:
• The Frontier Hard Chrome cleanup resulted in the maximum concentration of hexavalent chromium
of 300,000 ppb being reduced to below the federal MCL of 50 ppb—a nearly four orders of
magnitude reduction.
• The Gold Coast Oil Corp., FL remedy reduced initial maximum PCE concentrations of 100,000
ppb to less than 3 ppb (and below the EPA MCL of 5 ppb)—a four orders of magnitude reduction.
• The Island Chemical Corp. cleanup resulted in the total toluene/ ethylbenzene/xylene maximum
concentration of 176,000 ppb being decreased to 13 ppb (with all individual contaminant
concentrations below their federal MCLs)—a four orders of magnitude reduction.
• The Western Processing cleanup resulted in the maximum cis- 1,2-DCE concentration 10,000 ppb
in the offsite "trans" plume being decreased to non-detectable levels that were below the federal
MCL of 70 ppb—a three orders of magnitude decrease.
12
-------
Observations and Analysis
Figure 2.7 Magnitude of Contaminant Concentration Decreases at Sites that Achieved
Groundwater Restoration
Log (Maximum Concentration Before Treatment/Maximum Concentration After Treatment)
0 12 3 4
Del IMorte County Pesticide Storage, CA (OU 1)
Firestone Tire and Rubber, CA (OU 1)
Frontier Hard Chrome, WA (Oil's 1 and 2)
Gold Coast Oil Corp., FL (OU 1)
Island Chemical Corp, Virgin Islands (OU 1)
Mannheim Avenue Dump, NJ (OU 1)
Odessa Chromium II, TX (OU's 1-3)
Pasley Solvents and Chemicals, NY (OU 1)
Rochester Property, SC(OU 1)
SMS Instruments, NY (OU 1)
Visalia Pole Yard, CA(OU 1)
Tabernacle Drum Dump, NJ (OU 1)
Tri-StatePlating, IN (OU 1)
Vestal Water Supply Well 4-2, NY (OU 1)
Waverly Groundwater Contamination, NE(OU 1)
Western Pacific Railroad, CA (OU 1)
Western Processing, WA (OU 2) OffslteTrans Plume
Figure 2.8 shows the magnitude of contaminant
decreases for the 13 groundwater restoration sites
that achieved significant progress toward
groundwater restoration, which ranged from just
under one order at Browns Battery Breaking site to
more than three orders at the Eastern Surplus
Company site. The remedies that demonstrated the
greatest contaminant concentration decreases
included:
• TCE at the Fort Lewis Logistics Center, WA
East Gate Disposal Yard (Landfill 2) was
reduced from a maximum of 250,000 ppb to less
than 220 ppb maximum—a three orders of
magnitude reduction.
• TCE at Hollingsworth Solderless was reduced
from 4,300 ppb to below cleanup level of 3
ppb—a three orders of magnitude reduction.
'DNAPL (observed or suspected)
Significant Progress towards Groundwater
Restoration and Associated Cleanup Levels at the
Fort Lewis Logistics Center
Remedial actions at the Fort Lewis Logistics Center
East Gate Disposal Yard (Landfill 2) included the
cleanup of chlorinated VOCs and petroleum
hydrocarbons from soil and groundwater. This
contamination resulted from an industrial landfill
operated from 1946 to the early 1970's, where
degreasers from the Logistics Center were
transferred to drums and buried in trenches.
Chlorinated solvents were being released into the
City of Tillicum's public water supply. The remedy
included pump-and-treat. drum removal, and ISTT
(ERH) to treat source zones. These actions
reduced TCE concentrations by three orders of
magnitude, from 250,000 ppb to 220 ppb based on
the most current information available at the time
this report was prepared.
13
-------
Observations and Analysis
Figure 2.8 Magnitude of Contaminant Concentration Decreases at Sites that Achieved
Significant Progress towards Groundwater Restoration
Log (Maximum Concentration Before Treatment/Maximum Concentration After Treatment)
0
Browns Battery Breaking, PA (OU's 1 and 2)
Dover Air Force Base (AFB), SS07/Area 2, DE
Eastern Surplus Company, ME (OU 1)
East Gate Disposal Yard, WA (Landfill 2)
Hollingsworth Solderless Terminal, FL (OU 1)
King of Prussia, NJ (OU's 1-3)
LeHillier/Mankato Site, MN (OU 1)
Letterkenny Army Depot (Southeast Area), PA (OU 10)
Malvern TCE, PA (OU's 1-4)
Mystery Bridge Road (Dow), WY (OU's 1 and 2)
NCR Corp., DE (OU 1)
Pemaco, CA (OU 1)
US Aviex, Ml (OU 1)
* DNAPL (observed or suspected)
There was no obvious trend when the number of technologies used (Figure 2.4 and Figure 2.5) was
compared to the magnitude of contaminant decrease (Figure 2.7 and Figure 2.8). For example, at the
Frontier Hard Chrome site, a 3.8 order decrease in hexavalent chrome concentration was achieved using a
single technology (ISCR) whereas six technologies were employed at the Visalia Pole Yard site to achieve
a 2.8 order decrease in pentachlorophenol concentration. Also, there was no attempt to determine the
order of magnitude decrease in contaminant concentration achieved by each technology because the goal
of the Superfund program is to clean up sites. At some sites, this goal can be accomplished using a single
technology (e.g., Frontier Hard Chrome site); at other sites a combination of technologies was required to
achieve cleanup levels (e.g., Visalia Pole Yard).
2.4 Cleanup Time
The sites considered in this section are the 17 that achieved groundwater restoration (Table 2.1). Cleanup
time is given in Table A.4 and was defined as the time from the first application of a remedial technology
during the Superfund remedial action phase to the time when cleanup levels were first reported as having
been met. Cleanup time does not include the time for Superfund removal actions, attainment monitoring, or
the time required to propose and achieve delisting a site from the NPL because these times are unrelated
to remedial technology performance. Cleanup time ranged from three years at Tri-State Plating (OU 1) to
27 years at Del Norte Pesticide Storage with a median time of eight years. At the majority of sites (12 of
the 17 sites), groundwater restoration was achieved within 10 years while five sites required greater than
15 years to achieve groundwater restoration.
14
-------
Observations and Analysis
Cleanup time generally increased as cleanup magnitude increased (Figure 2.9). From Tri-State Plating
(OU1), where a cleanup of less than one order of magnitude contaminant concentration reduction was
completed in 3 years, to Western Processing (Offsite Trans Plume), where a cleanup of over 3 orders of
magnitude contaminant concentration reduction was completed in 24 years. The exceptions to this trend
were the four sites where contaminant concentrations decreased by nearly four orders of magnitude in less
than eight years (Frontier Hard Chrome, Gold Coast Oil Corp., Island Chemical, and Pasley Solvents and
Chemicals) and one site, Del Norte, where concentrations decreased by over 2 orders of magnitude, but
cleanup time was 27 years. The exact reason for the faster cleanup time at these four sites is not known.
However, the hydrogeologic setting is thought to play a key role in the time required to achieve
groundwater restoration13. In the case of Del Norte, the longer remediation time might be due to the more
recalcitrant contaminants (pesticides and herbicides combined with CVOCs). The hydrogeologic setting for
each of the 17 sites is also presented in Figure 2.9 and was determined from field investigation reports. Of
the 17 sites, eight have hydrogeologic settings that are generally less complex (Type I: mild heterogeneity
and moderate to high permeability), seven have more complexity (Type III: moderate to high heterogeneity
and moderate to high permeability), and two have hydrogeologic settings best described as being similar to
fractured media with high secondary porosity (Type V).
Cleanup times were generally shorter for sites with less complex hydrogeologic settings (Type I), including
Gold Coast Oil Corp. and Tri-State Plating sites where fewer than six years were required to meet cleanup
levels after remedial action was initiated. This was true for sites where DNAPL was suspected to be
present (Gold Coast Oil Corp. and Pasley Solvents) and sites with smaller plumes (Tabernacle Drum
Dump and Tri-State Plating). In addition, fewer technologies were employed (i.e., fewer than three) to
achieve groundwater cleanup levels for sites with less complex hydrogeologic settings (Type I). However,
there are exceptions to this trend. For example, SMS Instruments (OU1) required 16 years and the
application of four technologies to achieve groundwater restoration even though the hydrogeologic setting
consisted of fine- to coarse-grain sand with moderate to high permeability. In addition, two other Type I
sites, Del Norte and Waverly Groundwater Contamination, took 27 and 15 years respectively.
As the hydrogeologic setting became more complex (Type III and V), the time to achieve cleanup levels
generally increased. The cleanup time for the seven completed groundwater restoration remedies that
involved moderate to high heterogeneity and moderate to high permeability (Type III) ranged from six
years at Firestone Tire and Rubber to 24 years at Western Processing (OLJ 2, Offsite Trans Plume). These
sites had plumes of varying sizes (up to 2.5 miles long), depths (up to 250 feet bgs), and contaminant
groups (chlorinated VOCs, non-chlorinated VOCs, SVOCs or metals). However, the initial contaminant
concentrations and overall contaminant decreases for these sites were typically lower than for the Type I
sites. Sites with Type III setting and lower initial concentrations included:
• At Firestone Tire and Rubber, an initial 1,1-DCE concentration of 120 ppb was reduced to less than
6 ppb in a 2.5-mile long plume in six years.
• At the Mannheim Avenue Dump site, an initial TCE concentration of 140 ppb was reduced to below
1 ppb in a plume measuring 1,000 feet by 1,000 feet in area and extending 55 feet deep in eight
years.
13 Contaminants in the Subsurface: Source Zone Assessment and Remediation, Committee on Source Removal
of Contaminants in the Subsurface, National Research Council, 2004 (http://www.nap.edu/cataloq/11146.html)
15
-------
Observations and Analysis
Figure 2.9 Cleanup Time and Magnitude for Sites that Achieved Groundwater Restoration
30
25
-UT 20
1-
ru
£
aj 15
C 10
nj
Q)
U
•
/
Western Processing
(Offsite Trans Plume)
Del Norte County
Pesticide Storage
/
A
A
• •
\
SMS Instruments
¦ • Frontier Hard Chrome
Island
Chemical Corp
I
A •
Tri-State
•
•
Plating^*
Pasley Solvents and Chemicals y?
Gold Coast Oil
12 3 4
Cleanup Magnitude (Order of Magnitude)
• Granular Media with Mild Heterogeneity (Type I)
A Granular Media with Moderate to High Heterogeneity (Type III)
¦ Best Described as Fractured Media with High Matrix Porosity (Type V)
The one exception was the Western Processing site, which required 24 years to cleanup a plume with an
initial contaminant concentration of 10,000 ppb 1,1 -DCE, a higher initial concentration than the other Type
III sites, but lower than two of the Type I sites (Pasley Solvents and Gold Coast Oil Corp.).
The Rochester Property site in South Carolina, which consisted of a saprolite aquifer with silt and varying
amounts of fine to coarse sand and clays (Type V), achieved cleanup levels in nine years using air and
ozone sparging. Compared with the other sites shown in Figure 2.9, the Rochester Property site had a
relatively small contaminant plume (0.33 acres) and lower initial contaminant concentration (TCE
concentration of 180 ppb).
In terms of remedial technologies, the sites with a Type I hydrogeologic setting (Gold Coast Oil Corp.,
Pasley Solvents, Vestal, and Tabernacle Drum Dump) involved the remediation of chlorinated VOC plumes
(ranging in size from as small as 0.87 acres to approximately 3,000 feet long) using one or more of the
following: pump-and-treat, SVE and air sparging technologies. Several of the sites with a Type III
hydrogeologic setting (Firestone Tire and Rubber, Mannheim Avenue Dump, and Western Pacific
Railroad) also involved the application of pump-and-treat, SVE and air sparging technologies to remove
dissolved phase plumes that had affected at least two separate aquifer units of varying thickness and
composition. These data show that traditional technologies (pump-and-treat, SVE and air sparging) have
been effective at cleaning up dissolved phase contaminant plumes (e.g., chlorinated VOCs) and their
sources in permeable aquifers with mild to high heterogeneity.
16
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Reuse
3. Sites Returned to Use
Superfund Redevelopment14 operates as a nationally coordinated effort to ensure that at every Superfund
site, EPA and its partners have an effective process and the necessary tools and information needed to
return the country's most hazardous sites to productive use. Most of the sites (except Vestal Water Supply
Well 4-2 and Western Processing), have achieved the status of Sitewide Ready for Anticipated Use
(SWRAU). As described below, 12 of the 30 sites have been returned to use either in whole or in part. This
reuse has generated jobs, positively impacted local economies, and improved the quality of life for
neighboring communities. As shown in Table 3.1, and discussed below, the types of reuses that have been
implemented at the sites included in this report include industrial/commercial, recreational/wildlife
habitat/agricultural, mixed use, alternative energy development, and other reuses.
3.1 Industrial/Commercial Reuse
Industrial and commercial redevelopment was performed at eight of the sites included in this report. The
areas reused at these sites range from small single buildings (Browns Battery Breaking, PA) up to very large
land areas for industrial parks and mixed-use purposes (Firestone Tire and Rubber, CA). Specific examples
include:
• Browns Battery Breaking, PA - one-story
automobile and truck service and repair
facility.
• Firestone Tire and Rubber, CA - 256-acre
industrial park for several small- and
medium-size businesses.
• Norwood PCBs, MA - two single-story
retail buildings, totaling 56,000 square
feet,
• SMS Instruments, NY - kitchen,
bathrooms, and utensil manufacturer on a
1,5-acre parcel.
3.2 Recreational Use
Two sites have been reused as recreational parks (Pemaco, CA
and LeHillier/Mankato, MN).
3.3 Alternative Energy Development
Under the RE-Powering America's Land Initiative15, which was
launched in 2008, EPA and DOE have encouraged renewable
energy development on current and formerly contaminated land
and mine sites. The initiative identifies the renewable energy
potential of these sites and provides useful resources for
communities, developers, industry, state, and local governments
interested in reusing these sites for renewable energy
development. One of the Superfund sites evaluated in this report
14
For more information about the Superfund Redevelopment Initiative, see https://www.epa.gov/superfund-
redevelopment-initiative
15 RE-Powering America's Land Initiative encourages renewable energy development on current and formerly
contaminated lands, landfills, and mine sites when such development is aligned with the community's vision for
the site, see https://www.epa.gov/re-powering
Norwood PCBs Site, MA - Commercial Redevelopment
Superfund Site
17
-------
Reuse
participated in the RE-Powering Initiative in an effort to implement green and sustainable remedies.
• Pemaco, CA - installed a 3.4-kilowatt solar photovoltaic (PV) system in 2007 to help meet total
electricity demands of a high-vacuum dual-phase extraction system that removes TCE from perched
groundwater and upper vadose soil, and an ERH system that removes TCE from lower vadose soil
and groundwater. The solar PV system saves nearly $3,000 annually in electricity costs, and
reduces the site's greenhouse gas emissions by 3.3 tons each year.
3.4 Other Reuses
As shown in Table 3.1, a range of other reuses have also been implemented at the sites included in this
report. For example, the 5-acre Eastern Surplus Superfund Site in Maine, a former Army surplus and
salvage operation, includes a major archeological research site. During cleanup activities in the late 1990s,
EPA encountered a trove of American Indian artifacts and an archaeological site estimated to be thousands
of years old. EPA, in cooperation with the Passamaquoddy Tribe, Maine Department of Environmental
Protection, University of Maine, and the Maine Historic Preservation Commission, is preserving the historical
and cultural integrity of this property, including the collection of hundreds of stone tools, drills, pottery
shards, and scrapers typical of early eastern woodland tribes. At Western Processing, the cleanup of the
offsite plume led to surface water restoration.
Table 3.1 Sites Returned to Use
Reuse
Number
of Sites
Sites
Industrial/Commercial
8
Browns Battery Breaking, PA (OUs 1 and 2)
Firestone Tire and Rubber, CA (OU 1)
SMS Instruments, NY (OU 1)
Del Norte County Pesticide Storage, CA (OU 1)
Hollingsworth Solderless Terminal, FL (OU 1)
NCR Corp., DE (OU 1)
Norwood PCBs, MA(OU 1)
Pasley Solvents and Chemicals, Inc., NY (OU 1)
Recreational Use
2
Pemaco, CA (OU 1)
LeHillier/Mankato Site, MN (OU 1)
Alternative Energy
1
Pemaco, CA (OU 1)
Archaeological Research Site
1
Eastern Surplus Company, ME
Surface Water Restored
1
Western Processing, WA(OU 2), Offsite Trans Plume
18
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Conclusions
4. Conclusions
As detailed in this report, the Superfund program has overcome a range of challenges to achieve the
restoration of groundwater. The following are highlights from the previous sections:
• The most commonly occurring contaminants were chlorinated VOCs, which were present at 26 of
the 30 sites in this report. Metals were also prevalent, and were COCs at 12 of the 30 sites. The less
frequently occurring contaminants included non-chlorinated VOCs, SVOCs, and PCBs.
• The technologies applied to address groundwater contamination at the 30 NPL sites fit into 12
categories with pump-and-treat and excavation/removal the most commonly applied. Other
technologies associated with groundwater cleanups included SVE, MNA, capping, air sparging, in
situ bioremediation, ISCO, ISCR, ISTT, in situ pH adjustment, and VEBs.
• A combination of technologies was applied to address different media, multiple contaminants, or a
range of contaminant concentrations at 28 of the 30 sites. The most frequently used technology
combination was excavation/removal and pump-and-treat, which was used at 17 of the 30 sites.
Given that many of these sites were cleaned up during the period from 1983 to 2000, these
remedies represented state of the art technologies at that time.
• While traditional technologies such as pump-and-treat and air sparging achieved groundwater
restoration at some sites (e.g., Gold Coast, Firestone Tire and Rubber, Tabernacle Drum Dump, Tri-
State Plating), these technologies were modified or replaced with innovative technologies such as in
situ bioremediation, MNA, ISCO, and ISTT at some sites.
• The magnitude of contaminant concentration decreases for the sites that achieved groundwater
restoration ranged from just over one order at Firestone Tire and Rubber to more than four orders at
the Island Chemical Corp. site and Gold Coast Oil Corp. site. The magnitude of contaminant
decreases for the sites that have achieved significant progress toward groundwater restoration
ranged from just under one order at Browns Battery Breaking site to more than three orders at the
Eastern Surplus Company site.
• Although a combination of technologies was generally employed to achieve cleanup levels, there
was no obvious trend between the number of technologies used and the order of magnitude
decrease in contaminant concentration. At the Frontier Hard Chrome site, a single technology
(ISCR) was used to decrease hexavalent chromium by nearly four orders of magnitude. While at the
Visalia Pole Yard site, six different technologies were used to decrease pentachlorophenol
concentrations by nearly three orders of magnitude.
• The cleanup times for the 17 sites that achieved groundwater restoration ranged from three years at
Tri-State Plating (OU 1) to 27 years at Del Norte Pesticide Storage with a median time of eight
years. Cleanup time generally increased as cleanup magnitude increased at 12 of the 17 sites
except for four sites where contaminant concentrations were decreased by nearly four orders in less
than eight years. Cleanup times were generally shorter for sites with less complex hydrogeologic
settings apart from three sites that have mild heterogeneity and required more than 15 years to
achieve groundwater restoration. Also, in most cases, cleanup times were shorter for lesser
reductions in concentration.
• Most of the 30 sites, (except Vestal Water Supply Well 4-2 and Western Processing), have
achieved the of Sitewide Ready for Anticipated Use (SWRAU), and 12 of the 30 sites have been
returned to use either in whole or in part. Reuse includes industrial and commercial redevelopment,
recreational use, alternative energy use, archaeological research, surface water restoration, and
lifting of groundwater use restrictions.
19
-------
Appendices
Appendix A: Site Information Summary Tables
-------
Appendix A
Table A.1 Location, Industry Type, Contaminant Group, and Remedial Technology for NPL Sites that Achieved Groundwater
Restoration
industry Type
Contaminant Group
Technology
De! Norte County Pesticide Storage, CA (OU
1)
Firestone Tire and Rubber, CA (OU 1)
a.
E
"O
c
03
Frontier Hard Chrome, Inc., WA (OUs 1 and
2)
Gold Coast Oil Corp., FL (OU 1)
Island Chemical Corp/V.l. Chemical Corp,
USVI
Mannheim Avenue Dump, NJ
Odessa Chromium II, TX (OUs 1-3)
Pasley Solvents and Chemicals, Inc., NY
Rochester Property, SC (OU 1)
SMS Instruments, NY
Southern California Edison, Visalia Pole Yard,
CA (OU 1)
Tabernacle Drum Dump, NJ
Tri-State Plating, IN (OU 1)
Vestal Water Supply Well 4-2, NY
Waverly Groundwater Contamination, NE (OU
1)
Western Pacific Railroad, Co., CA (OU 1)
Western Processing, WA (OU2), Off site Trans
Plume
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o
03
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Restoration Totals
13
A-1
-------
Appendix A
Table A.2 Location, Industry Type, Contaminant Group, and Remedial Technology for NPL Sites that Achieved Significant
Progress towards Groundwater Restoration
Site
Industry Type
Contaminant Group
Technology
Landfill/Dump
Chemical Production
Manufacturing
Metal Works/Plating
Waste TSD
Military/Federal
Wood Treatment
Other
Chlorinated VOCs
Metals
Non-chlorinated VOCs
PCBs/Pesticides/Dioxins/
Furans
PAHs/SVOCs/
Excavati o n/Re mova I
Pump-and-Treat
Capping
SVE
In Situ Bioremediation
Air Sparging
MNA
VEB
ISCO
ISCR
In Situ Thermal Treatment
In Situ pH Adjustment
Browns Battery Breaking, PA (OUs 1 and 2)
•
•
•
•
•
Dover AFB - SS07/Area 2, DE
•
•
•
Eastern Surplus Company, ME
•
•
•
•
•
Fort Lewis Logistics Center, WA (East Gate
Disposal Yard, Landfill 2)
•
•
•
•
Hollingsworth Solderless Terminal, FL (OU1)
•
•
•
•
•
King of Prussia, NJ
•
•
•
•
•
•
•
LeHillier/Mankato Site, MN (OU 1)
•
•
Letterkenny Army Depot (Southeast Area),
PA (OU10)
•
•
•
•
•
Malvern TCE, PA (OUs 1-4)
•
•
•
•
•
•
•
•
Mystery Bridge Road/Highway 20 (Dow/DSI),
WY (OUs 1 and 2)
•
•
•
•
•
NCR Corp., DE
•
•
•
•
•
•
Pemaco, CA(OU 1)
•
•
•
•
•
•
•
US Aviex, Ml (OU 1)
•
•
•
•
•
•
•
Restoration Totals
1
2
2
1
2
3
0
2
11
4
6
2
2
9
9
2
5
5
2
5
0
3
2
2
1
A-2
-------
Appendix A
Table A.3 Summary of Technologies Applied to Restore Groundwater
Site
RAO / Cleanup
Goal Status
Technologies Used
Gold Coast Oil Corp., FL
(OU 1)
Achieved
Initial remedial actions included the excavation/removal and disposal of visibly contaminated soil, followed by
installation of a groundwater pump-and-treat system. Attempts to enhance contaminant reduction during pump-
and-treat operation, first by the addition of hydrogen peroxide and then by pulsed pumping, were unsuccessful.
The pump-and-treat system was shut down and additional soil excavation/removal and air sparging of
groundwater (without pump-and-treat) in two areas of suspected DNAPL were subsequently performed. Several
adjustments, both successful and unsuccessful, were made to the pump-and-treat system to optimize and speed
cleanup. Some groundwater extraction wells were enlarged to increase extraction rates in the most contaminated
area of the plume. Additionally, hydrogen peroxide was injected into these two wells in an unsuccessful attempt to
oxidize TCE and PCE. The groundwater extraction system was shut down periodically (or pulsed) for periods of
30 and 60 days in an attempt to increase TCE and PCE desorption from aquifer materials in area groundwater.
Contaminant concentrations were not significant reduced and the pump-and-treat system was permanently shut
down. The soil was then excavated in suspected hot spots. Finally, air sparging was used in suspected hot spots
to reduce residual contamination to below cleanup levels.
Odessa Chromium II, TX
(OUs 1-3)
Achieved
The initial remedy included the extraction of chromium-contaminated groundwater with ex situ electrochemical
treatment of groundwater with chromium concentrations greater than the MCL. At the time of the initial remedy,
the cleanup level for total chromium was 0.05 ppm, but was later raised to 0.10 ppm. Treated groundwater was re-
injected. The treatment system was expanded to remediate an additional contaminant plume and the treatment
type was changed from electrochemical to ion exchange to reduce costs. Two wells remained above cleanup
levels after five years of extraction and treatment. ISCR using Fe(ll)S04 treatment was applied at the two
remaining wells to speed the remediation process, reducing concentrations to below cleanup levels.
Rochester Property, SC (OU
1)
Achieved
An air sparging system was operated at the site for four years to treat TCE, when it was determined that
groundwater on-site met cleanup levels. However, groundwater sampling and analysis found increasing
contaminant concentrations in a down gradient well off-site. The air sparging system was then modified to include
ozone sparging. The air/ozone sparging system reduced off-site groundwater contaminant concentration to below
cleanup levels.
Southern California Edison,
Visalia Pole Yard, CA (OU
1)
Achieved
Remedial actions at the site included installing a VEB (slurry wall) around the contaminated area and
excavation/removal of contaminant sources. A groundwater pump-and-treat system was also operated for 19
years to remediate the groundwater plume. In situ thermal treatment using DUS was installed to increase the rate
of recovery of contaminants and reduce cleanup costs. After the DUS system was shut down, in situ
bioremediation (including vadose zone bioventing and saturated zone biosparging) was applied with pump-and-
treat. The bioremediation phase took advantage of the elevated subsurface temperatures to enhance the
biological degradation process. A post-remediation soil investigation indicated that TCDD was detected slightly
above the cleanup level at four locations. As a result, soil within the TCDD "hot spot" areas was removed. This
combination of remedies achieved all cleanup levels.
Western Pacific Railroad
Co., CA (OU 1)
Achieved
A pump-and-treat system was used at this site to treat groundwater contaminated with CVOCs. The pump-and-
treat system was modified multiple times during the cleanup, including replacing GAC units with an air stripper to
remove contaminants from extracted groundwater, and adding a new extraction well. SVE was also added to
expedite and optimize contaminant removal. This approach achieved all cleanup levels.
A-3
-------
Appendix A
Site
RAO / Cleanup
Goal Status
Technologies Used
Browns Battery Breaking,
PA (OUs 1 and 2)
Significant
Progress
In situ injection of sodium bicarbonate was used to lower metal concentrations in both alluvial and upper bedrock
groundwater through 2013, but additional reductions were not observed from 2013 through 2016. Pneumatic
fracturing of wells occurred in March 2017 to increase the delivery of sodium bicarbonate the aquifer. Additional
information about the effect of hydro-fracturing was not yet available at the time this report was published.
Eastern Surplus Company,
ME
(OU 1), Southern TCE
Plume
Significant
Progress
A removal action included excavation/removal and off-site disposal of contaminated soil and sediment and
groundwater pump-and-treat with reinjection of the treated water. Addition of permanganate to the reinjected
water was done to enhance the remedy, which began during the removal action phase. A later ROD selected this
remedy and it continued in the remedial action phase. Six additional extraction wells were added to increase
flushing of the plume, and sodium permanganate solution was injected in direct push wells with additional
permanganate solution added to re-circulating wells. PCE concentrations increased after permanganate
injections, and then declined for five consecutive sampling events. The groundwater pump-and-treat system was
shut down for a short period to evaluate how contaminant concentrations would change or rebound in response to
ISCO. The system was restarted after groundwater sampling data indicated that concentrations had increased in
both plumes. Extraction wells located within the southern plume were shut down after VOC concentrations later
decreased to the cleanup levels.
Fort Lewis Logistics Center,
WA (East Gate Disposal
Yard, Landfill 2)
Significant
Progress
A pump-and-treat system was used at this site to remove TCE from groundwater. The pump-and-treat system was
updated by decommissioning and replacing the original extraction wells and reconfiguring the extraction well and
reinjection networks to optimize plume containment and contaminant mass removal. In addition, in situ thermal
treatment was performed using ERH. The ERH enhanced contaminant removal by volatilizing chemicals and
decreasing fluid viscosity, which allowed for extraction of LNAPL and DNAPL. An additional pump-and-treat
system was installed and continues to operate along with the original pump-and-treat system.
Hollingsworth Solderless
Terminal, FL (OU 1)
Significant
Progress
A groundwater pump-and-treat system was operated for two years, when it was determined that the system was
no longer effective at further reducing concentrations of TCE, c/s-1,2-DCE and VC. Subsequent groundwater
monitoring results showed a rebound of contaminant concentrations. An in situ pilot test for enhanced
bioremediation was completed in September, 2007. Additional soil excavation/removal was conducted, and in situ
bioremediation (potassium lactate injections and bioaugmentation) was implemented in 2013. The most recently
available groundwater monitoring data (June 2016) indicates that VC is the only contaminant exceeding cleanup
levels. Only 1 out of the 24 wells being monitored exceeds the State of Florida VC standard of 1 ppb, with
concentrations measuring 45ppb.
King of Prussia, NJ (OUs 1-
3)
Significant
Progress
A pump-and-treat system was used to initially capture contamination but concentrations of some chlorinated
VOCs and metals remained above cleanup levels. In March 2013, ISCR was conducted with carbon impregnated
zero valence iron substrate. From October 2002 through September 2003 ISCO with hydrogen peroxide and
ferrous sulfate was applied in a separate area. Contaminant concentrations are continuing to diminish, and
monitoring at the site is ongoing.
A-4
-------
Appendix A
Site
RAO / Cleanup
Goal Status
Technologies Used
Pemaco, CA (OU 1)
Significant
Progress
Soil excavation/removal and an SVE system were installed to remediate chlorinated and non-chlorinated VOCs.
However, community concerns about potential dioxin emissions from thermal oxidation treatment of extracted
vapors led to the shutdown of the SVE system. A high vacuum dual-phase extraction (HVDPE) pump-and-treat
system which used granulated activated carbon (GAC) for groundwater treatment and flameless thermal oxidation
(FTO) and GAC for treatment of vapors was installed. In addition, ERH was used to treat the deeper vadose soils
and groundwater from 32 to 100 feet bgs, followed by groundwater pump-and-treat and MNA. EPA conducted an
RSE in 2011 to optimize the system, and issued an RSE report in July 2011, which contained recommendations
for reducing sampling, and optimizing system design and equipment, but did not contain recommendations for
changing the remedy. Many of the recommended optimizations have been implemented16. However, groundwater
cleanup levels are not being met as contamination levels have been increasing since 2011 because the full extent
of TCE contamination has not been determined.
16 Appendix to the Groundwater Remedy Optimization. Progress Report: 2010 - 2011
A-5
-------
Appendix A
Table A.4 Time to Meet RAOs and Hydrogeologic Complexity for Sites that Achieved Groundwater Restoration
Site Name
Groundwater
Contaminant Groups
(Contaminants with
Highest
Concentrations)
Remedies that
Contributed to
Groundwater
Cleanup
Areal Extent of
Plume
Hydrogeologic Complexity of Contaminated
Aquifer
Years to
Meet
Cleanup
Levels
Del Norte County
Pesticide Storage,
CA (OU 1)
Pesticides, Herbicides,
Chlorinated VOCs (1,2-
DCP, 2,4-D)
Excavation, Pump-and-
Treat, MNA
Not available
Type 1: moderately well-sorted fine sands,
silts, and clays with generally moderate groundwater
permeability.
27
Firestone Tire and
Rubber, CA(OU 1)
Chlorinated VOCs, Non-
chlorinated VOCs
(Benzene, 1,1-DCE, 1,1-
DCA, PCE, Toluene, TCE,
Xylene)
Pump-and-treat
2.5 mile long plume
Type III'. Three aquifers (shallow, intermediate, and
deep) each with sands and gravels, and conductivity of
>100 ft day. Each aquifer is separated from the
neighboring aquifer by discontinuous clay aquitards,
which consist of impermeable silt and clay units.
Groundwater extracted from each of the three aquifers.
6
Frontier Hard
Chrome, Inc., WA
(OU's 1 and 2)
Metals (Trivalent and
Hexavalent Chromium)
In situ redox
manipulation treatment
wall to reduce Cr6
(injection of sodium
dithionite reagent).
Not available
Type III: Upper zone is low permeability silty sandy
gravel, underlain by high permeability sandy gravel and
sand silt leaky aquitard. Lower zone is moderate to high
permeability sandy gravels.
8
Gold Coast Oil
Corp., FL (OU 1)
DNAPL, Chlorinated
VOCs, Non-chlorinated
VOCs (PCE, TCE, trans-
1,2-DCE, 1,1 -DCA,
Methylene Chloride,
Toluene)
Excavation, pump-and-
treat, air sparging
0.87 acre areal
extent and up to 10
feet thick
Type /: Unconfined aquifer of white to light tan, fine-
grained sand with high permeability.
6
Island Chemical
Corp/V.l. Chemical
Corp, Virgin Islands
(OU 1)
Non-chlorinated VOCs,
Chlorinated VOCs, Metals
(Methylene chloride,
Chloroform, Ethylbenzene,
Xylenes, Toluene,
Acetone)
SVE, air sparging, MNA
Not available
Type III'. Brown and gray clay-rich alluvial sediments.
Local lenses of permeable gravel and sand are located
at approximately 30 to 40 ft bgs. Underlying the
alluvium is the white to light brown and gray, lime-rich,
stiff clay of the Kinphill Formation.
6
Mannheim Avenue
Dump, NJ (OU 1)
Chlorinated VOCs, Metals
(TCE, Lead)
Excavation, pump-and-
treat, MNA,
[Point of entry treatment
systems installed in
1993,
Plume measuring
1,000 feet x 1,000
feet in area and
extending 55 feet
deep
Type III'. The aquifer underlying the site consists of
shallow and deep zones, each comprised of sand and
gravel, separated by an approximately 3 to 5 feet thick
semi-permeable clay layer.
8
Odessa Chromium
II, TX (OUs 1-3)
Metals
(Hexavalent Chromium)
Pump-and-treat, ISCO
with ferrous sulfate
Approximate 40 acre
plume
Type V\ Sandstone and conglomerate rock overlaid by
soil and caliche
10
A-6
-------
Appendix A
Site Name
Groundwater
Contaminant Groups
(Contaminants with
Highest
Concentrations)
Remedies that
Contributed to
Groundwater
Cleanup
Areal Extent of
Plume
Hydrogeologic Complexity of Contaminated
Aquifer
Years to
Meet
Cleanup
Levels
Pasley Solvents
and Chemicals,
Inc., NY (OU 1)
DNAPL, Non-chlorinated
VOCs, Chlorinated VOCs
(trans- 1,2-DCE, TCA, 1,1-
DCA, Chlorobenzene,
Toluene, Ethylbenzene,
Xylenes)
SVE, air sparging
400-foot-long plume,
depths up to 60 feet
Type /: Unconsolidated sand and gravel
5
Rochester
Property, SC (OU
1)
Chlorinated VOCs, PAH,
Metals [TCE, c/s- 1,2-DCE,
£>/s(2-ethylhexyl)phthalate)
manganese]
Excavation, air
sparging, ISCO using
ozone sparging.
0.33 acres
Type V: Saprolite aquifer with silt and varying amounts
of fine to coarse sand and clays.
9
SMS Instruments,
NY (OU 1)
Chlorinated VOCs, non-
chlorinated VOCs (TCE,
Chlorobenzenes, Xylene)
pump-and-treat, SVE,
air sparging
Not available
Type 1: moderate to high permeability, Stratified fine- to
coarse-grained sand and light to dark tan or brown
gravel
16
Southern California
Edison, Visalia Pole
Yard, CA(OU 1)
DNAPL, CSVOCs,
SVOCs, PCP, Dioxins
[Benzo(a)pyrene, TCDD]
In situ thermal
treatment, enhanced in
situ bioremediation (air
sparging and
bioventing), pump-and-
treat, VEB (slurry wall),
excavation
SVOC plume covers
2.1 acres and
extends from water
table to depth of
approximately 145
feet
Type III'. Three aquifers (shallow, intermediate, and
deeper) consisting of unconsolidated sediment lie
beneath the site, ranging in depth from 30 to 180 feet
bgs. Aquitards consisting of a relatively impermeable
silt layer separate these aquifers
19
Tabernacle Drum
Dump, NJ (OU 1)
Chlorinated VOCs
(TCA, 1,1-DCE)
Removal of drums,
excavation of soil,
pump-and-treat
Plume extended ~
3,000 feet from
source area
Type /: Generally homogeneous sand that becomes
coarser with depth and an average value of hydraulic
conductivity of 343.5 gpd/sq ft (SEMS 56482)
4
Tri-State Plating, IN
(OU 1)
Metals (Chromium)
Pump-and-treat,
excavation, drum
removal,
decontamination and
demolition of site
buildings
200-foot long plume
Type /: Unconfined aquifer composed of alternating
sequences of sand and gravelly sands with high
permeability where hydraulic conductivity values
ranged from 1 to 7 x 10-2 cm/sec and averaged about
3.5 x 10-2 cm/sec (SEMS 221436)
3
Vestal Water
Supply Well 4-2,
NY (OU 1)
Chlorinated VOCs (TCA,
TCE, PCE)
Pump-and-treat
Not available
Type 1: Glaciofluvial sand and gravel deposits
9
Waverly
Groundwater
Contamination, NE
(OU 1)
Chlorinated VOCs (Carbon
Tetrachloride, Chloroform)
SVE, pump-and-treat
Not available
Type 1: Site is underlain by about 13 feet of loess and
over 80 feet of sand in two layers separated by
approximately 5 feet of clay, contamination was in
upper aquifer (SEMS 40193838). Estimated
transmissivity values range from 25,000 to greater than
100,000 gallons per day per foot. (SEMS 40184729)
16
A-7
-------
Appendix A
Site Name
Groundwater
Contaminant Groups
(Contaminants with
Highest
Concentrations)
Remedies that
Contributed to
Groundwater
Cleanup
Areal Extent of
Plume
Hydrogeologic Complexity of Contaminated
Aquifer
Years to
Meet
Cleanup
Levels
Western Pacific
Railroad Co., CA
(OU 1)
Chlorinated VOCs (1,1-
DCE, 1,1 -DCA, TCE)
Pump-and-treat, SVE
700-foot long plume
extending 60 feet
bgs
Type ill'. Interbedded clays, sands, and gravels, which
vary in thickness and composition, both horizontally
and vertically across the site
6
Western
Processing, WA
(OU 2), Offsite
Trans Plume
Chlorinated VOCs, Metals
(TCE, c/'s-1,2-DCE, vinyl
chloride, Zinc)
Pump-and-treat, slurry
wall, capping, MNA.
Not available
Type III: A fairly continuous fine to medium sand with
intermittent silty zones existing below 40 feet. This sand
unit extends to a depth of 150 feet below ground
surface. Conductivity of 10 to 100 feet/day (FRTR Case
Study)
24
Notes:
(1) Hydrogeologic complexity and extent of plume are based on the information provided in the resources used to develop this report.
(2) Restoration time presented in this report begins when the first Superfund Remedial Action phase began, including source removals such as excavation or drum removal.
For completed restorations, the restoration time ends when the concentration goals were first reported as being met.
(3) Hydrogeologic categories are described in Contaminants in the Subsurface: Source Zone Assessment and Remediation, Committee on Source Removal of
Contaminants in the Subsurface, National Research Council, 2004 (http://www.nap.edu/catalog/11146.html).
A-8
-------
Appendix A
Table A.5 Time to Achieve Significant Progress and Complexity for Selected Sites that Achieved Significant Progress towards
Groundwater Restoration
Site Name
Groundwater
Contaminant Groups
(Contaminants with
Highest
Concentrations)
Remedies that
Contributed to
Groundwater
Cleanup
Areal Extent of
Plume
Hydrogeologic Complexity of
Contaminated Aquifer
Years to Meet
Cleanup Levels
Dover Air Force
Base (AFB), DE
(SS07/Area 2,
South
Management Unit)
DNAPL, Chlorinated VOCs
(PCE, TCE, c/s-1,2-DCE,
Vinyl Chloride)
ERD/Accelerated
anaerobic
biodegradation, MNA
Approximately 2,800
feet long by 650 feet
wide
Layered/lnterbedded'. Four (4) aquifers
beneath site with varying compositions
including mixtures of gravel, sand, and
silt with clay and gravel lenses
11 +
Eastern Surplus
Company, ME
(OU 1), Southern
TCE Plume
Chlorinated VOCs (PCE,
TCE)
Soil excavation and
waste removal, pump-
and-treat, ISCO with
sodium permanganate
injections
1.5 acre southern
chlorinated VOC plume;
depths up to 20-30 feet
bgs
Layered/lnterbedded'. Overburden
consisting of stratified beds of gravel,
sand, and mixed sands and silt, and
shallow bedrock
11
Fort Lewis
Logistics Center,
WA (East Gate
Disposal Yard
(EGDY) OU1)
DNAPL, LNAPL, Chlorinated
VOCs, Petroleum
Hydrocarbons (TCE)
Pump-and-treat, drum
removal, in situ thermal
treatment (ERH)
TCE groundwater
plume extended 2 to 2.5
miles long and 3,000 to
4,000 feet wide, with
60-to-100-foot
contaminant thickness
Layered/lnterbedded'. Complex
hydrostratigraphy generally consisting
of glacial sand and gravel deposits with
till layers overlying a finer-grained
nonglacial deposit
25+
Hollingsworth
Solderless
Terminal, FL (OU
1)
Chlorinated VOCs (TCE, cis-
1,2-DCE, Vinyl Chloride)
Excavation, pump-and-
treat, SVE, in situ ERD
(with potassium lactate
and bacteria injections)
Approximate 200-foot
radius area (or about 3
acres), with the highest
concentrations found at
the 50-to-75-foot depths
Homogeneous, Medium to High
Permeability. Site overlies Biscayne
aquifer, which is highly permeable,
unconfined, and composed of a fine- to-
medium grained sand, sandstone, and
limestone sequence
26+
Letterkenny Army
Depot (Southeast
Area), PA (OU 10)
Chlorinated VOCs (TCE,
frans-1,2-DCE, Vinyl
Chloride)
ERD using sodium
lactate injections, MNA
Chlorinated VOC
groundwater plume
extends to springs
located approximately
1.5 to 2 miles off-site
Fractured'. Fractured and weathered
karstic bedrock, with large cavities
formed by dissolution of limestone rock
18+
Pemaco, CA (OU
1)
DNAPL, Chlorinated VOCs
(PCE, TCE, c/s-1,2-DCE,
Vinyl Chloride), Non-
chlorinated VOCs
SVE, in situ thermal
treatment (ERH), high-
vacuum dual phase
extraction, pump-and-
treat, and MNA
Chlorinated VOC
groundwater plume
approximately 1,300
feet by 750 feet in deep
aquifer, extended 200
feet offsite in perched
aquifer
Layered/lnterbedded'. Six discrete
groundwater zones, including perched
aquifer and five underlying zones made
up of silty sands separated by less
permeable clay-rich strata
10+
Notes:
(1) For ongoing remedies that have not yet met RAOs, the time in years to meet them is followed by a
A-9
-------
Appendix A
Table A.6 Site Information Summary Table
| « S 8 o
i M SI
ra 2 ra 1 =
SO sS 8
O o S o
— o
o
» -o aT
"Si ii .2 g ^
Oa^ES
2 i<
«0»o
°2 £
Eastern Surplus
Company, ME
EPA Region 1
Other
(Salvage/
Storage
Yard/
Re-sale)
Groundwater
Soil
Sediment
Chlorinated
VOCs, Metals,
PCBs (PCE,
TCE,
Manganese,
Lead, PCBs)
Restore groundwater
to meet MCLs or
Maine Maximum
Exposure Guidelines
(MEGs) (PCE 3 ppb).
Prevent additional
sediment
contamination and
offsite migration.
Significant progress
has been made.
Soil excavation
and waste
removal, pump-
and-treat, ISCO
with sodium
permanganate
injections.
Removed
approximately
120 transformers,
4,650 gallons of
waste oil, and
2,400 gallons of
PCB oil.
PCE concentrations in 1.5 acre
Southern Plume reduced from
1,100 ppb to below cleanup
level. Chlorinated VOC
concentrations in Northern
Plume are still above cleanup
levels. Current site use includes
a major archaeological research
site for the history of the
Passamaquoddy people.
Listed
06/17/1996;
Not yet
deleted
See Case Summary for full
list of information sources.
1. EPA Web site:
Eastern Surplus Company
Site Profile
King of Prussia,
NJ (OUs 1-3)
EPA Region 2
Waste TSD
Soil /
Groundwater
Chlorinated
VOCs, Metals,
SVOCs (PCE,
TCE, DCE,
Chloroform,
Beryllium,
Copper,
Chromium,
Nickel,
Phthalates)
Remediate soils
through either
treatment or
excavation and offsite
disposal to meet EPA
risk-based cleanup
levels, and restore
groundwater to state
and federal MCLs
(PCE 1 ppb, TCE 1
ppb).
Significant progress
has been made.
Pump-and-treat,
excavation, ex situ
soil washing, ISCR
with carbon
impregnated zero
valance iron
substrate, ISCO
with hydrogen
peroxide and
ferrous sulfate.
Disposed of 2
tankers and over
500 drums/
containers
holding
contaminated
materials. Over
19,000 tons of
metals-
contaminated
soils treated with
soil washing.
Over 729 million
gallons of
groundwater
treated with
pump-and-treat
system, removing
1.27 tons of
chlorinated VOCs
and 5.6 tons of
metals.
Soil remedy achieved risk-based
cleanup levels and eliminated a
major source of groundwater
contamination. Pump-and-treat
is providing capture but
concentrations of some
chlorinated VOCs and metals
(chromium and beryllium) remain
above cleanup levels. In 2014,
average PCE concentrations
were 18 ppb. Average TCE
concentrations were 10.2 ppb.
ISCO reduced VOC
concentrations in monitoring and
recovery wells by 81 % to 97%.
Listed
09/01/1983;
Not yet
deleted
1. EPA Web site: King of
Prussia Site Profile
2. Five-Year Review Report.
King of Prussia Superfund
Site (Sept 2010):
3. Five-Year Review Report.
King of Prussia Superfund
Site (June 2015)
A-10
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Appendix A
— V) U)
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Oa^ES
2 |< g£
«0»o
°2 £
Mannheim
Avenue Dump,
NJ (OU 1)
EPA Region 2
Landfill/
Dump
Soil /
Groundwater
Chlorinated
VOCs, Metals
(TCE, Lead)
Restore groundwater
to a NJDEP TCE
cleanup level of 1 ppb.
RAOs have been
achieved.
Excavation, pump-
and-treat, MNA.
Over 25,000
pounds of
contaminated
sludge and 2,700
CY of
contaminated soil
removed. RAOs
met in
approximately 8
years of
combined pump-
and-treat and
MNA.
TCE in groundwater reduced
from 140 ppb to less than
cleanup level. Eliminated TCE
plume initially measuring 1,000
feet x 1,000 feet in area and
extending 55 feet deep.
Listed
09/01/1983;
Deleted
08/28/2007
See Case Summary for full
list of information sources.
1. EPA Web site: Mannheim
Avenue Dump Site Profile
Tabernacle
Drum Dump, NJ
(OU 1)
EPA Region 2
Landfill/
Dump
(Rural area
with a one-
time
dumping of
solvents,
paints, and
paint
sludge)
Soil /
Groundwater
Chlorinated
VOCs (TCA,
DCE)
Restore groundwater
to meet state MCLs
(TCA 26 ppb, DCE 2
ppb).
RAOs have been
achieved.
Removal of drums,
excavation of soil,
pump-and-treat.
Removed and
disposed of 40
CY of drummed
material, 8
truckloads of soil,
and 3,000 gallons
of liquid material.
Seven million
gallons of
impacted
groundwater
treated per
month, achieving
RAOs in just over
4 years of pump-
and-treat.
TCA reduced from 1,000 ppb to
less than NJDEP MCL, and DCE
reduced from 180 ppb to less
than NJDEP MCL. Eliminated
chlorinated VOC plume that
initially extended ~ 3,000 feet
from the source area.
Listed
09/21/1984;
Deleted
05/08/2008
See Case Summary for full
list of information sources.
1. EPA Web site: Tabernacle
Drum Dump Site Profile
Pasley Solvents
and Chemicals,
Inc., NY (OU 1)
EPA Region 2
Chemical
Production
(Oil/Solvent
Storage and
Distribution)
Soil /
Groundwater/
DNAPL
(suspected)
VOCs,
Chlorinated
VOCs (DCE,
TCA, DCA,
Chlorobenzene,
Toluene,
Ethyl benzene,
Xylenes)
Restore groundwater
to MCLs (DCE 100
ppb, TCA 200 ppb).
Treat soil to residential
risk levels (1 ppm).
RAOs have been
achieved.
SVE, air sparging.
Over 15,000
pounds of
contaminants
removed from
soil and
groundwater.
Cleanup levels
achieved within 5
years of AS/SVE
system startup.
Soil cleanup levels met. Total
VOC concentrations in
groundwater dramatically
reduced from 37,000 ppb to 4
ppb. DCE reduced from 25,000
ppb to below MCL. TCA reduced
from 3,600 ppb to below MCL.
400-foot long plume reduced to
below MCLs.
Listed
06/10/1986;
Deleted
09/26/2011
See Case Summary for full
list of information sources.
1. EPA; DNAPL
Remediation: Selected
Projects Where Regulatory
Closure Goals Have Been
Achieved: pps. 47-48;
2009b.
2. Second Five-Year Review
Report for Pasley Solvents
and Chemicals Site; 2009.
A-11
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Appendix A
— V) U)
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2 |< g£
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°2 £
SMS
Instruments, NY
(OU 1)
EPA Region 2
Manufacturi
ng (Military
Aircraft
Component
s -Industrial
Wastes)
Soil /
Groundwater
Chlorinated
VOCs, non-
chlorinated VOCs
(TCE,
Chlorobenzenes,
Xylene)
Restore groundwater
to meet federal and
state MCLs.
RAOs have been
achieved.
Tank removal,
pump-and-treat,
SVE, air sparging
6,000 gallon
underground tank
removed. 50,000
tons of soil
remediated.
Approximately
607 million
gallons of
groundwater
treated.
Initial total chlorinated VOC
concentrations exceeded 5,000
ppb near the source area. Post
treatment, total chlorinated VOC
concentrations in groundwater
were reduced to around 10 ppb,
with individual contaminants
below their respective cleanup
levels. A kitchen, bathroom, and
household utensil manufacturer,
operates on the site today.
Listed
06/10/1986;
Deleted
09/13/2010
1. EPA Web site: SMS
Instruments Inc. Site Profile
2. Third Five Year Review
Report for SMS Instruments
Site (May 2006)
Vestal Water
Supply Well 4-2,
NY (OU 1)
EPA Region 2
Chemical
Production
(Distribution
)
Soil /
Groundwater
Chlorinated
VOCs (TCA,
TCE, PCE)
Restore groundwater
to MCLs.
RAOs have been
achieved.
Excavation, pump-
and-treat.
42 tons of
contaminated
materials
removed. 6,950
million gallons of
contaminated
groundwater
treated.
Initial maximum groundwater
concentrations of TCA (390
ppb), TCE (239 ppb), and PCE
(220 ppb) from municipal well 4-
2 decreased to levels below
drinking water standards.
Treatment period occurred over
approximately 9 years.
Listed
09/01/1983;
Deleted
09/30/1999
1. Charsky, Matthew;
Science and Policy Branch,
Groundwater Successes at
Deleted NPL Sites. (2010)
2. EPA Web site: Vestal
Water Supply Well 4-2 Site
Profile
3. Lee, G. W.
Hydrogeological
Investigation of Organic
Contamination at Monarch
Chemicals, Inc. Town of
Vestal. (1980)
Island Chemical
Corp/V.l.
Chemical Corp,
Virgin Islands
(OU 1)
EPA Region 2
Chemical
Production
(Pharmaceu
tical
manufacturi
ng and
blending
operations)
Soil /
Groundwater
Non-chlorinated
VOCs,
Chlorinated
VOCs, Metals
(Methylene
chloride,
Chloroform,
Ethyl benzene,
Xylenes,
Toluene,
Acetone)
Restrict on-site
groundwater use to
non-potable purposes
until MCLs are
achieved.
RAOs have been
achieved.
SVE, air sparging,
MNA
Removed 205
55-gallon drums,
40 85-gallon
drums, 9 5-gallon
drums of various
chemicals, and
8,000 pounds of
lab pack
chemicals from
buildings. 2,030
pounds of
contaminants
removed from
groundwater.
Groundwater concentrations of
total toluene, ethylbenzene and
xylene reduced from a maximum
of 176,000 ppb to 13 ppb.
Chloroform concentrations in
groundwater reduced from 2,400
ppb to 13 ppb. All contaminant
concentrations meet MCL
cleanup levels.
Listed
06/17/1996;
Deleted
10/16/2009
1. EPA Web site:
Island Chemical Corp/VI
Chemical Corp. Site Profile
2. Five-Year Review Report
for Island Chemical Corp.
Virgin Islands Chemical
Corp. Superfund Site (March
2009)
A-12
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Appendix A
— V) U)
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2 |< g£
«0»o
°2 £
Dover Air Force
Base (AFB),
SS07/Area 2,
South
Management
Unit, DE (OU
15)
EPA Region 3
Military/Fed
eral (Aircraft
Maintenanc
e)
Groundwater
/DNAPL
(suspected)
Chlorinated
VOCs (PCE,
TCE, DCE, VC)
Restore groundwater
to meet state MCLs (1
ppb PCE, TCE, and
VC), prevent exposure,
and restrict land use to
industrial until
unrestricted exposure
and use levels can be
documented.
Significant progress
has been made.
ERD/Accelerated
anaerobic
biodegradation,
MNA.
Over 100,000
gallons of carbon
substrate injected
into subsurface
through 49
injection points,
resulting
favorable
conditions for
reductive
dechlorination.
ERD resulted in
meeting cleanup
levels in most
SS07 source
area wells within
2 years. The
plume was
initially 2,800 feet
long and 650 feet
wide.
In 2006, PCE and TCE
concentrations were 32,000ppb
and 110 ppb, respectively. By
2008 nearly all wells met
cleanup levels. However, the
most recent semi-annual
monitoring data (January 2016)
indicated exceedances in 2
source area wells. In one well
TCE, 1,2-DCE and VC were 86
ppb, 840 ppb and 130 ppb,
respectively. At the other well
TCE and VC were 23 ppb and
8.2ppb, respectively. These
wells are being resampled to
confirm concentrations.
Listed
03/13/1989;
Not yet
deleted
See Case Summary for full
list of information sources.
1. EPA Web site: Dover Air
Force Base Site Profile
2. Fourth Five-Year Review
Report for Dover AFB,
SS07/Area 2, South
Management Unit (Sept
2013)
2 Monitoring Report Sites
SS07, LF17, and LF18South
Management Unit (through
October 2010) (February
2011)
4. Monitoring Report Sites
SS07, LF17, and LF18South
Management Unit (through
December 2014) (March
2015)
4. Dover AFB Sampling
Summary Report SS07 (not
yet in a report)
NCR Corp., DE
(OU 1)
EPA Region 3
Manufacturi
ng
(Electronic
Equipment)
Groundwater/
DNAPL
(suspected)
Chlorinated
VOCs (TCE)
Prevent offsite
migration and reduce
groundwater
concentrations to meet
MCLs (TCE 5 ppb).
Significant progress
has been made in the
Phase I and II areas
of the site.
Pump-and-treat,
SVE, air sparging,
in situ biological
reductive
dechlorination (full
scale), ZVI (ISCR).
Approximately
315 CY of sludge
and wastes from
concrete lagoons
and pits was
excavated.
In situ and ex situ groundwater
treatment has prevented offsite
migration and substantially
reduced levels of TCE in both
Phase I and II areas
groundwater, where TCE
concentrations have been
reduced from >490,000 ppb to a
range from less than 5 ppb in the
Phase I area and 200 ppb in the
Phase II area . Contaminants
still exceed cleanup levels in 3
wells.
Listed
07/22/1987;
Not yet
deleted
1. EPA Web site: NCR Corp.
Site Profile
2. Second Five-Year Review
for NCR Corporation (June
2005)
3. Third Five-Year Review
Report for NCR Corporation
Superfund Site (July 2010)
4. Semi-Annual Report for
the Millsboro, Delaware, NPL
Site, TRC Environmental
Corporation (July 2013)
5. Fourth Five-Year Review
for NCR Corporation
Superfund Site (June 2015)
A-13
-------
Appendix A
Site Name
Industry (Site
Type)
Media
Contaminant
Groups
(Contaminants
with Highest
Concentrations)
RAOs /
Cleanup Levels
(RAOs Achieved or
Significant
Progress Made)
Remedial
Technologies Used
Magnitude of
Cleanup
Progress/
Accomplishments
NPL Listing;
Deletion
Information
Source(s)
Browns Battery
Metal
Soil /
Metals (Lead,
Relocation of
Consolidation and
Approximately
Soil RAOs have been met. Lead
Listed
1. EPA Web site: Brown's
Breaking, PA
Works/
Groundwater
Zinc, Beryllium,
residents, removal of
capping soil and
13,000 cubic
concentrations in soil have been
06/10/1986;
Batterv Breakina Site Profile
(OUs 1 and 2)
Plating
Cadmium,
contamination from
battery
yards of battery
reduced from maximum of
Not yet
2. Third Five Year Review
(Battery
Chromium,
onsite soils, restore
casings,
casings and
60,000 ppm to below cleanup
deleted
Report for Brown's Batterv
EPA Region 3
Recycling
Nickel)
groundwater to
excavation offsite
contaminated soil
level of 1,000 ppm. Cleanup
Site (Sept 2007)
Facility)
background levels and
disposal of soils,
consolidated and
levels for metals have not been
3. Fourth Five-Year Reoort
pH between 6-8, meet
stabilization/solidifi
capped.
met site wide, but metals plume
for Brown's Battery Site
federal and state MCLs
cation,
Disposed of
has been reduced to 100 foot in
(Sept 2012)
(lead 5 ppb).
in situ injection of
25,000 tons of
radius. A contaminated
4. Ruth Associates, Inc.,
Significant progress
sodium
stabilized
groundwater plume remains with
Results of the February 2016
has been made.
bicarbonate to
material. Treated
max lead concentrations of 17
Groundwater Monitoring
elevate pH
and disposed of
ppb. In-situ injection of sodium
Event; Brown's Battery
of groundwater.
43,000 tons of
bicarbonate lowered metal
Breaking Site; April 19, 2016.
Pneumatic
soil and battery
concentrations in both alluvial
fracturing of wells
casings. Between
and upper bedrock groundwater
completed in
2003 and 2007,
through 2013, but additional
March 2017
28 injection
reductions were not observed
to attempt to
events and a total
from 2013 through 2016.
increase
of 70,601 pounds
the delivery of
of sodium
sodium
bicarbonate
bicarbonate the
added to the
aquifer.
groundwater
within the target
area.
A-14
-------
Appendix A
Site Name
Industry (Site
Type)
Media
Contaminant
Groups
(Contaminants
with Highest
Concentrations)
RAOs /
Cleanup Levels
(RAOs Achieved or
Significant
Progress Made)
Remedial
Technologies Used
Magnitude of
Cleanup
Progress/
Accomplishments
NPL Listing;
Deletion
Information
Source(s)
Letterkenny
Military/
Groundwater
Chlorinated
Meet federal and State
In situ biological
Over an 18 year
TCE and VC concentrations
Listed
See Case Summary for full
Army Depot
Federal
VOCs, Non-
MCLs for groundwater
treatment using
period, remedy
reduced from a maximum of 67
07/22/1987;
list of information sources.
(Southeast
(Ammunition
Chlorinated
and PA Water Quality
ERD with sodium
has reduced
ppb and 90 ppb, respectively to
Not yet
1. EPA Web site:
Area), PA (OU
Storage)
VOCs (TCE,
Criteria (WQC) for
lactate injections,
onsite
below MCLs. Originally, the
deleted
Letterkennv SE Area Site
10)
DCE, VC, and
springs. Reduce or
MNA.
groundwater
plume was greater than 20 acres
Profile
Benzene)
eliminate migration of
contaminant
but since 2013 all chlorinated
2. ESP. Southeastern (SE)
EPA Region 3
contaminated
concentrations
solvent concentrations are below
Area OU Letterkenny Army
groundwater off-post
significantly.
MCLs. However, benzene
Depot (Sept 2009)
and to off-post springs.
Concentrations in
exceeds the MCL in 1 well.
3. Five-Year Review Reoort
Return land to
down gradient
Groundwater use restrictions
for Letterkenny SE Area Site
beneficial use.
offsite wells and
were lifted from some of the on-
(Sept 2012)
Significant progress
springs are below
post and off-post areas of OU
4. Annual Groundwater and
has been made.
MCLs and water
10.
Surface Water Monitoring
quality criteria,
Report for SE Area OU 10
respectively.
(August 2016)
5. Five-Year Review Report
for Letterkenny Army Depot
(March 2017)
A-15
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Appendix A
— V) U)
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2 |< g£
«0»o
°2 £
Malvern TCE,
PA (Oils 1-4)
EPA Region 3
Waste TSD
(Solvent
Reclamation
Facility)
Soil /
Groundwater/
DNAPL
(suspected)
Chlorinated
VOCs, non-
chlorinated
VOCs, PCBs
(TCE, PCE, TCA,
1,4-Dioxane)
Prevent direct contact
with contaminated soils
and reduce potential
migration of
contaminants to
groundwater, prevent
ingestion and
inhalation of
contaminants in
groundwater, restore
groundwater to
beneficial use and to
meet MCLs (FDA/MA
area: TCE 5 ppb, cis-
1,1-DCE 7 ppb; MPA:
TCE 5 ppb, cis-1,1-
DCE 7 ppb).
Significant progress
has been made.
Structure/tank/dru
m and soil
excavation and
removal and offsite
disposal, cap,
SVE, in situ
bioremediation
recirculation
system (using
sodium lactate and
nutrient injections),
MNA.
250 poly drums,
50 steel drums, 5
tanks, 8 fire
extinguishers, 2
propane tanks,
and 2
pressurized
cylinders were
removed. 143 CY
of PCB-impacted
soils excavated.
More than 11,000
pounds of
chlorinated and
non-chlorinated
VOCs removed
from soils by SVE
system since
2005.
Chlorinated VOC concentrations
in residential wells reduced
below MCLs in early 2000's and
have been non-detect ever
since. In the FDA/MA Area
concentrations of TCE (240 ppb
down to 23 ppb), cis-1,2 DCE
(1,000 ppb down to 100 ppb),
and 1,4-dioxane (56 ppb down to
11 ppb) have decreased by
about an order-of-magnitude
since 2005 due to MNA. In just 2
years of operation in the Main
Plant Area (MPA), the in situ
bioremediation system has
shown a 2-3 order-of-magnitude
reduction in source area TCE
and TCA groundwater
concentrations. Initial TCE
concentrations have been
reduced from 81,400 ppb to d
2,170 ppb; c/s-DCE
concentrations have been
reduced from 77,000 ppb to d
3,150 ppb; and TCA
concentrations have been
reduced from 6,800 ppb to d 580
ppb. COC concentrations remain
above cleanup levels, although
the remedial system has
achieved a significant reduction
of COCs. In the FDA/MA area,
max VOC concentrations are
4,886 ppb, decreased from
35,146 ppb in 2007. In the MPA
area, TCE concentrations are
down to a max of 530 ppb.
There has been an overall 76-
90% reduction of VOC
concentrations in the MPA area.
Listed
09/08/1983;
Not yet
deleted
1. EPA Web site: Malvern
TCE Site Profile
2. Second Five-Year Review
Report for Malvern TCE
Superfund Site (Sept 2010)
3. Third Five-Year Review
Report for Malvern TCE
Superfund Site (Sept 2015)
A-16
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Appendix A
— V) U)
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2 |< g£
«0»o
°2 £
Gold Coast Oil
Corp., FL (OU
1)
EPA Region 4
Waste TSD
(Oil/Solvent
Reclamation
)
Groundwater/
Soil /
DNAPL
(suspected)
Chlorinated
VOCs, VOCs
(PCE, TCE, DCE,
DCA, Methylene
Chloride,
Toluene)
Restore groundwater
to MCLs.
RAOs have been
achieved.
Excavation, pump-
and-treat, air
sparging.
883 tons of
contaminated soil
removed. 80
million gallons of
groundwater
treated and 1,961
pounds of PCE
and TCE
removed. Met
cleanup levels
within 6 years of
initiating remedial
actions.
PCE concentrations in
groundwater reduced from
100,000 ppb to below 3 ppb;
TCE reduced from 48,000 ppb to
below 3 ppb. Remedy reduced
initial 0.87 acre plume to below
cleanup levels.
Listed
09/08/1983;
Deleted
10/09/1996
See Case Summary for full
list of information sources.
1. Ryan, Serena; NNEMS,
DNAPL Cleanup:
Accomplishments at Twelve
NPL Sites. (August 2010)
2. EPA Web site: Gold Coast
Oil Company Site Profile
Hollingsworth
Solderless
Terminal, FL
(OU 1)
EPA Region 4
Manufacturi
ng
(Solderless
Electrical
Terminals)
Soil /
Groundwater
Chlorinated
VOCs (TCE, cis-
DCE, Vinyl
chloride)
Restore groundwater
to meet federal and
state MCLs and risk-
based cleanup levels
(TCE 3 ppb, cis-DCE
70 ppb, VC 1 ppb).
Significant progress
has been made.
Excavation, pump-
and-treat, SVE, in
situ bioremediation
with ERD using
potassium lactate
and bacteria
injections
Over 300 tons of
contaminated
soils removed.
Pump-and-treat
system initially
removed up to 55
pounds of
contaminants per
day.
TCE reduced from 4,300 ppb to
below cleanup level, and cis-
DCE reduced from 10,000 ppb
to below cleanup level. VC as
high as 6,000 ppb have been
reduced to 45 ppb. VC is the
only remaining groundwater
contaminant detected above
state or federal standards. Most
recent groundwater monitoring
results (June 2016) indicate only
1 well of 24 exceed state of FL
standard of 1 ppb for VC.
Listed
09/08/1983;
Not yet
deleted
See Case Summary for full list of
information sources.
1. EPA Web site: Hollingsworth
Solderless Site Profile
2. EPA Region 4, June 2016
Rochester
Property, SC
(OU 1)
EPA Region 4
Landfill/
Dump
Soil /
Groundwater
Chlorinated
VOCs, non-
chlorinated
SVOCs, Metals
(TCE, DCE,
Bis(2-
ethylhexyl)phthal
ate, Manganese)
Restore groundwater
to MCLs (TCE 5 ppb,
manganese 180 ppb,
c/s-1,2-DCE 70 ppb).
RAOs have been
achieved.
Excavation, air
sparging, ISCO
using ozone
sparging.
Removed 1,400
CY of
contaminated
soils. Air and
ozone sparging
achieved MCLs
over 9 years
TCE reduced from 180 ppb to
below 5 ppb, manganese
reduced from 1,390 ppb to below
cleanup level, and cis-1,2-DCE
reduced from 3,600 ppb to below
MCL. TCE plume eliminated
from initial size of ~ 1/3 acre.
Site meets criteria of "Site-Wide
Ready for Anticipated Use".
Listed
10/04/1989;
Deleted
10/09/2007
See Case Summary for full
list of information sources.
1. Charsky, Matthew;
Science and Policy Branch,
Groundwater Successes at
Deleted NPL Sites. (2010)
2. EPA Web site: Rochester
Property Site Profile
A-17
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Appendix A
— V) U)
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Oa^ES
2 |< g£
«0»o
°2 £
Tri-State
Plating, IN (OU
1)
EPA Region 5
Metal
Works/
Plating
(Electroplati
ng)
Soil /
Groundwater
Metals
(Chromium)
Eliminate the source
and restore
groundwater to federal
MCLs (chromium 50
ppb).
RAOs have been
achieved.
Pump-and-treat,
excavation, drum
removal,
decontamination
and demolition of
site buildings.
27 drums of toxic
materials
removed. Top 1
foot of soil and
visibly-
contaminated
areas excavated.
All on-site
structures
demolished. 200
gpm pump-and-
treat system
reduced
chromium
concentrations to
below 50 ppb
cleanup level in
three years of
operation.
Chromium reduced from
maximum concentration of 1,800
ppb to less than cleanup level.
Remedy eliminated 200-foot
long chromium plume. Site
meets criteria for "Site-Wide
Ready for Anticipated Use".
Listed
06/10/1986;
Deleted
07/14/1997
See Case Summary for full list of
information sources.
1. EPA Web site: Tri-State
Plating Site Profile
US Aviex, Ml
(OU 1)
EPA Region 5
Chemical
Production
(Automobile
fluid
production;
bulk
chemical
repackaging
)
Soil /
Groundwater
Chlorinated
VOCs, Non-
chlorinated VOCs
(TCE, PCE,
1,1,1-TCA,
Diethyl ether, 1,2-
DCA, 1,1-DCE)
Restore groundwater
to levels established by
MDEQ and MCLs (1,2-
DCA 5 ppb, diethyl
ether 43 ppb, TCE 5
ppb, PCE 0.88 ppb,
TCA 200 ppb). Provide
onsite control of
contaminated
groundwater to prevent
its migration offsite.
Significant progress
has been made.
Soil excavation,
pump-and-treat,
air sparging, ISCO
using ozone
sparging, MNA.
4,817 tons of soil
excavated and
hauled offsite.
Contaminated
groundwater
plume extended
~ 1 mile from
facility.
As of 6/2009, in situ groundwater
treatment reduced all
contaminant concentrations to
below MCLs with the exception
of 1,2-DCA, Diethyl ether, TCE,
PCE and TCA, which have been
decreasing. COCs persist above
cleanup levels within the
contaminant plume
downgradient of the site. In
January 2013, EPA issued a
Site-wide Ready for Anticipated
Reuse (SWRAU) determination.
Listed
09/08/1983;
Not yet
deleted
1. EPA Web site: U.S. Aviex
Site Profile
2. Third Five-Year Review
Report for U.S. Aviex
Superfund Site (Nov 2009)
3. Fourth Five-Year Review
Report for U.S. Aviex
Superfund Site (Nov 2014)
A-18
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Appendix A
— V) U)
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«0»o
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LeHillier/
Mankato Site,
MN (OU 1)
EPA Region 5
Landfill/
Dump
Groundwater
Chlorinated
VOCs (TCE)
Protect public from
exposure to TCE,
minimize migration of
TCE in groundwater,
and restore
groundwater to federal
MCLs (TCE 5 ppb).
Significant progress
has been made.
Pump-and-treat.
Treatment of a
50-acre TCE
plume in shallow
unconfined
aquifer over 8
years of pump-
and-treat.
Extraction wells
designed to
operate at rates
up to 500 GPM.
Reduced initial TCE
concentrations of up to 300 ppb
to below MCL in 15 of 16 wells.
Remaining well has TCE
concentration of 12.6 ppb.
Nearby municipal well shows no
detections of TCE or chlorinated
VOCs.
Listed
09/08/1983;
Not yet
deleted
1. EPA Web site:
Lehillier/Mankato Site Profile
2. Fourth Five-Year Review
Report for Lehillier/Mankato
Superfund Site (June 2011)
3. Fifth Five-Year Review
Report for Lehillier/Mankato
Superfund Site (June 2016)
Odessa
Chromium II, TX
(OUs 1-3)
EPA Region 6
Manufacturi
ng (Radiator
repair
facility)
Groundwater
Metals
(Hexavalent
Chromium)
Prevent human
ingestion of
contaminated water
and restore
groundwater to meet
federal MCLs (total
chromium 0.1 ppm).
RAOs have been
achieved.
Pump-and-treat, in
situ chemical
reduction (ISCR)
with ferrous sulfate
treatment
121 million
gallons of
groundwater
pumped and
treated, removing
141 pounds of
chromium. ISCR
with ferrous
sulfate used to
address residual
chromium
contamination in
two wells.
Cleanup levels
achieved in less
than 10 years of
combined pump-
and-treat and
ISCR.
Total chromium reduced from
9.9 ppm to less than MCL.
Remedy reduced approximate
40 acre chromium plume to
below MCLs.
Listed
05/20/1986;
Deleted
07/19/2004
See Case Summary for full
list of information sources.
1. EPA Web site: Odessa
Chromium II Site Profile
2. Five Year Review Report
for Odessa Chromium II
Superfund Site (2001)
A-19
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Appendix A
— V) U)
| „ I 8 I
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O O s o
— o
£ -o a.
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Oa^ES
2 |< g£
«0»o
°2 £
Waverly
Groundwater
Contamination,
NE (OU 1)
EPA Region 7
Other (Grain
Facility)
Soil /
Groundwater
Chlorinated
VOCs (Carbon
Tetrachloride,
Chloroform)
Prevent exposure to
contaminated
groundwater, prevent
future migration of
contaminated
groundwater plume,
restore contaminated
groundwater for future
use as drinking water
by reducing CCI4 and
chloroform to below
risk-based criteria
(CCI4 5 ppb,
chloroform 3.8 ppb).
RAOs have been
achieved.
SVE, pump-and-
treat.
GW treatment
system designed
to accept a flow
of 400 GPM and
an extraction well
pumping rate of
150 GPM.
Maximum CCI4 and chloroform
concentrations detected in
groundwater were 400 ppb and
200 ppb, respectively. CCI4
reduced to 2.6 ppb, below
cleanup level. Chloroform
reduced to below cleanup level.
Listed
06/10/1986;
Deleted
11/20/2006
1. EPA Web site: Waverly
Groundwater Contamination
Site Profile
2. Fourth Five-Year Review
Report for Waverly
Groundwater Contamination
Site (Aug 2009)
3. Third Five-Year Review
Report for Waverly
Groundwater Contamination
Site (Sept 2004)
Mystery Bridge
Road/Highway
20 (Dow/DSI),
WY (OUs 1 and
2)
EPA Region 8
Other (Oil
Field
Services)
Soil /
Groundwater
Chlorinated
VOCs, VOCs,
LNAPL (PCE,
Benzene,
Toluene,
Ethyl benzene,
and Total
Xylenes [BTEX])
Prevent ingestion of
contaminated
groundwater and
restore affected aquifer
by reducing
contaminant
concentrations to meet
federal MCLs (PCE 5
ppb).
Significant progress
has been made.
Excavation, pump-
and-treat, , SVE
440 CY
contaminated soil
removed and
disposed offsite.
SVE system
recovered 6,300
pounds of VOC
contaminants.
Cleanup levels have been met
with most recent sampling data
showing that all COCs are below
MCLs.
Listed
08/30/1990;
Not yet
deleted
1. EPA Web site: Mystery
Bridge Road/Highway 20
Site Profile
2. Third Five-Year Review
Report for Mystery Bridge
Road/Highway 20 Superfund
Site, Natrona County,
Casper, Wyoming (Sept
2009)
3. Fourth Five-Year Review
Report for Mystery Bridge
Road/Highway 20 Superfund
Site (Sept 2014)
4. Isoconcentration Map of
PCE and Benzene in
January 2010
A-20
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Appendix A
— V) U)
| „ I 8 I
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O O s o
— o
£ -o a.
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Oa^ES
2 |< g£
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Del Norte
County
Pesticide
Storage, CA
(OU 1)
EPA Region 9
Chemical
Production
(Storage of
pesticides)
Soil /
Groundwater
Pesticides,
Herbicides,
Chlorinated
VOCs (1,2-DCP,
2,4-D)
Restore groundwater
to MCLs. Technical
Impracticability waiver
in 2000 ROD
amendment waived the
5 ppb MCLfor 1,2-
DCP. The 1985 ROD
established the RAO
for 1,2-DCP at 10 ppb.
Soil and groundwater
RAOs have been
achieved for all
contaminants of
Excavation and
offsite disposal for
soil, pump-and-
treat, MNA.
Removed 290 CY
of contaminated
soil. 23 million
gallons of
groundwater has
been treated over
7 years. 98%
reduction of 1,2-
DCP
concentrations.
Reduced 1,2-DCP concentration
in groundwater from 2,000 ppb
to below MCL. 2,4-D reduced to
below its MCL of 100 ppb
through source removal alone.
Upon confirmation by future
sampling that 1,2-DCP
concentration remains below the
MCL
Listed
09/21/1984;
Deleted
09/18/2002
See Case Summary for full
list of information sources.
1. EPA Web site: Del Norte
County Pesticide Storage
Site Profile
2. Five-Year Review Report
for Del Norte County
Pesticide Storage Site (June
2015)
Firestone Tire
and Rubber, CA
(OU 1)
EPA Region 9
Manufacturi
ng (Tire)
Soil /
Groundwater
Chlorinated
VOCs,
nonchlorinated
VOCs (Benzene,
DCE, DCA, PCE,
Toluene, TCE,
Xylene)
Reduce contaminant
concentrations to meet
CA state drinking water
cleanup levels or risk-
based levels and
control contaminant
migration (DCE 6 ppb).
RAOs have been
achieved.
Excavation and
capping, pump-
and-treat
Removed 22
storage tanks
and 5,300 CY of
contaminated
soil. 1.8 billion
gallons of
groundwater
treated. 496
pounds of
chlorinated and
non-chlorinated
VOCs removed.
Achieved cleanup
levels in
approximately 6
years of pump-
and-treat.
DCE concentration reduced from
120 ppb to less than cleanup
level. Remedy reduced 2.5 mile
long groundwater contaminant
plume to below cleanup levels.
Site has been returned to
productive use as an industrial
park that provides space for
several small and medium-size
businesses.
Listed
07/22/1987;
Deleted
04/21/2005
See Case Summary for full
list of information sources.
1. EPA Web site: Firestone
Tire and Rubber Site Profile
A-21
-------
Appendix A
Site Name
Industry (Site
Type)
Media
Contaminant
Groups
(Contaminants
with Highest
Concentrations)
RAOs /
Cleanup Levels
(RAOs Achieved or
Significant
Progress Made)
Remedial
Technologies Used
Magnitude of
Cleanup
Progress/
Accomplishments
NPL Listing;
Deletion
Information
Source(s)
Pemaco, CA
Chemical
Soil /
Chlorinated
Prevent migration of
Excavation and
Removal and
Groundwater TCE in the in situ
Listed
See Case Summary for full
(OU 1)
Production
Groundwater/
VOCs, Non-
COCs from soil to
off-site disposal of
treatment of
thermal treatment area reduced
01/19/1999;
list of information sources.
(Blending
DNAPL
chlorinated
groundwater. Restore
soil, SVE, in situ
21,500 pounds of
from 22,000 ppb to 660 ppb and
Not yet
1. Ryan, Serena; NNEMS,
EPA Region 9
and
(suspected)
VOCs, SVOCs,
groundwater to MCLs
thermal treatment
chlorinated VOCs
DCE was reduced from 14,000
deleted
DNAPL Cleanup:
Distribution)
Metals, PAHs
(TCE 5 ppb, DCE 6
(ERH), high-
in vadose zone
ppb to 440 ppb. The site was
Accomolishments at Twelve
(PCE, TCE, DCE,
ppb). Prevent offsite
vacuum dual
soils. DNAPL
redeveloped into a park. A 3.4-
NPL Sites. (Auaust 2010)
Vinyl chloride)
migration of
phase extraction,
remediated.
kW PV system produces
2. EPA : Pemaco Maywood
contaminated
groundwater. Eliminate
potential exposures to
indoor air
contamination.
pump-and-treat,
and MNA.
approximately 5,600 kWh/yr.
Groundwater cleanup levels
have not been met as
contaminant levels have been
Profile Site
3. Groundwater Monitoring
Report, 2013 June
Monitoring Event (April 2014)
Significant progress
has been made.
increasing since 2011.
4. Second Five-Year Review
Report, Pemaco Superfund
Site, Los Angeles County,
California. Sept. 2015.
A-22
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Appendix A
— V) U)
| „ I 8 I
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ra 2 ra 1 =
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Oa^ES
2 |< g£
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Southern
California
Edison, Visalia
Pole Yard, CA
(OU 1)
EPA Region 9
Wood
Treatment
Soil /
Groundwater/
DNAPL
Chlorinated and
non-chlorinated
SVOCs, PCP,
dioxins
(Benzo(a)pyrene,
TCDD)
Discontinue discharge
of chemicals related to
pole treatment
operations, extract and
treat contaminated
groundwater to meet
MCLs (PCP 1 ppb,
BaP 0.2 ppb, TCDD
0.00003 ppb), and
contain the
contaminant plume.
RAOs have been
achieved.
In situ thermal
treatment,
enhanced in situ
bioremediation (air
sparging and
bioventing), pump-
and-treat, VEB -
slurry wall,
excavation.
1.33 million
pounds of
contaminants
removed or
treated by series
of remedies. In
situ thermal
treatment
removed over
99% of
contamination in
just three years.
Cleanup levels
and RAOs across
site met in less
than 25 years
from start of
remediation.
Cleanup of
groundwater
plume covering
2.1 acres and
extending from
the water table to
a depth of
approximately
145 feet.
PCP concentration reduced from
maximum concentration of 610
ppb to below MCL. BaP
concentration reduced from
maximum of 5 ppb to below
MCL. TCDD concentration
reduced from maximum of 11
ppb to MCL.
Listed
03/31/1989;
Deleted
09/25/2009
See Case Summary for full
list of information sources.
1. Ryan, Serena; NNEMS,
DNAPL Cleanup:
Accomplishments at Twelve
NPL Sites. (August 2010)
2. EPA; DNAPL
Remediation: Selected
Projects Where Regulatory
Closure Goals Have Been
Achieved. (2009) 3.
EPA Web site: Southern
California Edison Site Profile
Western Pacific
Railroad Co.,
CA (OU 1)
EPA Region 9
Other (Rail
Facility)
Soil /
Groundwater
Chlorinated
VOCs, Metals,
SVOCs (DCE,
DCA, TCE,
Arsenic, Lead,
PAHs)
Restore groundwater
to federal and state
MCLs (DCE 6 ppb,
DCA 5 ppb).
RAOs have been
achieved.
Excavation, pump-
and-treat, SVE.
2,500 tons of
PAH
contaminated soil
removed. 127
million gallons of
groundwater
treated. 66
pounds of
chlorinated VOCs
removed from
soil and
groundwater. Site
was deleted from
NPL 11 years
after remedial
actions began.
DCE concentration reduced from
320 ppb to 1.7 ppb, less than CA
MCL. DCA concentration
reduced from 66 ppb to 1.4 ppb,
less than CA MCL. Remedy
eliminated initial 700-foot long
chlorinated VOC contaminant
plume.
Listed
08/30/1990;
Deleted
08/29/2001
See Case Summary for full
list of information sources.
1. Charsky, Matthew;
Science and Policy Branch,
Groundwater Successes at
Deleted NPL Sites. (2010)
2. EPA Web site: Western
Pacific Railroad Co Site
Profile
A-23
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Appendix A
— V) U)
| „ I 8 I
IH si
ra 2 ra 1 =
go sS 8
O O s o
— o
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"Si ii .2 g ^
Oa^ES
2 |< g£
«0»o
°2 £
Fort Lewis
Logistics
Center, WA
(East Gate
Disposal Yard
(EGDY)/Landfill
2
EPA Region 10
Military/
Federal
(Maintenanc
e and
Disposal
Yard)
Soil /
Groundwater/
DNAPL/
LNAPL
Chlorinated
VOCs, Petroleum
Hydrocarbons
(TCE)
Restore groundwater
to MCLs (TCE 5 ppb).
Significant progress
has been made.
Pump-and-treat,
drum removal, in
situ thermal
treatment with
electrical resistive
heating (ERH).
Over 125,000
pounds of
chlorinated VOCs
and petroleum
hydrocarbons
removed by ERH
over three year
period. 12,787
pounds of
chlorinated and
non-chlorinated
VOCs extracted
from pump-and-
treat.
Maximum TCE concentrations in
treatment zone fell from 250,000
ppb to a maximum concentration
of 220 ppb. Site received the
fiscal year 2005 Secretary of
Defense Environmental Award
for Environmental Restoration.
Listed
11/21/1989;
Not yet
deleted
See Case Summary for full
list of information sources.
1. Ryan, Serena; NNEMS,
DNAPL Cleanup:
Accomplishments at Twelve
NPL Sites. (August 2010)
2. EPA Web site: Fort Lewis
Logistics Center Site Profile
3. 2015 Remedial Action
Completion Report for Joint
Base Lewis McChord
Logistics Center (Aug 2015)
4. Preliminary site close-out
report for Fort Lewis
Logistics Center Site Profile
(Sept 2015)
5. United States Department
of Army; 2014 Annual
Groundwater Monitoring
Report. (July, 2016)
Frontier Hard
Chrome, Inc.,
WA (O's 1 and
2)
EPA Region 10
Metal
Works/
Plating
(Chrome
Plating)
Soil /
Groundwater
Metals (Trivalent
and Hexavalent
Chromium)
Prevent direct
exposure to chromium-
contaminated soils and
dust, control source
area, and meet federal
MCLs for chromium
(50 ppb).
RAOs have been
achieved for soil (OU
1) and groundwater
(OU2). Attainment
assessment is
underway.
In situ soil mixing
with injection of
reducing agent in
the source area. In
situ redox
manipulation
treatment wall to
reduce Cr6
(injection of
sodium dithionite
reagent).
Over 180,000
gallons of
groundwater
treated through
injection
technology. 160
CY of
contaminated soil
excavated and
disposed off site.
Initial chromium concentrations
in groundwater as high as
300,000 ppb. Groundwater
concentrations in all monitoring
wells have been below the
cleanup level since 2009.
Listed
09/08/1983;
Proposed for
deletion in
2017.
1. EPA Web site: Frontier
Hard Chrome Inc. Site
Profile
2. Five-Year Review Report
for Frontier Hard Chrome,
Inc (2008)
3. Long-Term Monitoring
Report Event 19 for Frontier
Hard Chrome Site (June
2013), Washington
Department of Ecology, (Dec
2011.)
4. Five-Year Review for
Frontier Hard Chrome, Inc
(Jan 2013)
5. Long-Term Monitoring
Report for Frontier Hard
Chrome Inc. (Dec 2014)
A-24
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Appendix A
Site Name
Industry (Site
Type)
Media
Contaminant
Groups
(Contaminants
with Highest
Concentrations)
RAOs /
Cleanup Levels
(RAOs Achieved or
Significant
Progress Made)
Remedial
Technologies Used
Magnitude of
Cleanup
Progress/
Accomplishments
NPL Listing;
Deletion
Information
Source(s)
Western
Waste TSD
Groundwater/
Chlorinated
Prevent offsite
Pump-and-treat,
"Trans" plume
Slurry wall, pump-and-treat, and
Listed
1. Ryan, Serena; NNEMS,
Processing, WA
Soil /
VOCs, Metals
migration of
slurry wall,
actively
MNA program reduced "trans"
09/08/1983;
DNAPL Cleanuo:
(OU 2), Offsite
Surface
(TCE, cis-1,2-
contaminated
capping, MNA.
remediated by
plume groundwater
Not yet
Accomolishments at Twelve
Trans Plume
Water
DCE, Vinyl
groundwater through
pump-and-treat
concentrations outside slurry
deleted
NPL Sites. (Auqust 2010)
Chloride, Zinc)
containment (1995
for 12 years
wall to safe drinking water levels.
2. EPA Web site: Western
EPA Region 10
ESD). Performance
(1988-2000)
No chlorinated VOCs were
Processina Co. Site Profile
standard for "trans"
and MNA from
detected in "trans" plume
3. Fourth Five-Year Review
plume groundwater is
2000 to present.
monitoring wells in 2010. Last
Reoort for Western
MCLs for c/s-1,2-DCE
40-foot deep
detection of TCE in 1992, 1,2-
Processing Superfund Site
(70 ppb). Restore
slurry wall
DCE in 2002, and vinyl chloride
(July 2008):
surface water to
installed to
in 2006. Initial maximum
4. 2010 Annual Report
Federal Ambient Water
prevent
groundwater DCE and vinyl
Western Processing Kent,
Quality Criteria
contaminants
chloride concentrations in "trans"
Washington, Landau
(AWQC) (or
from migrating
plume wells were approximately
Associates (June 2011)
background-derived
offsite. 13-acre
10,000 ppb and 500 ppb,
concentrations where
RCRA cap
respectively. Surface water
5. Fifth Five-Year Review
upstream
placed over site.
contaminants have met cleanup
Report for Western
concentrations
As of 2010, over
levels since 1993.
Processing Superfund Site
approach or exceed
11,000 pounds of
(Sept. 2013)
the AWQC).
TCE, 5,500
RAOs have been
pounds of DCE,
achieved.
1,000 pounds of
vinyl chloride,
and 81,000
pounds of metals
have been
extracted from
the groundwater.
A-25
-------
Appendix B
Appendix B: Case Summaries
B-1
-------
Appendix B
Table B-1. Industry Type, Media, Contaminant, and Technology for 19 Remedies with Case Summaries
Site
Page Number
Industry (Site
Type)
Media Type
Contaminant
Groups
(Contaminants
with Highest
Concentrations)
Technology
Region 1
Eastern Surplus Company,
ME (OU 1), Southern TCE
Plume
B-6
Other (Salvage/Storage
Yard/Re-sale)
Groundwater/Soil/Sediment
Chlorinated VOCs,
Metals, PCBs (PCE,
TCE, Manganese, Lead,
PCBs)
Soil and sediment
excavation and waste
removal, pump-and-treat,
ISCO with sodium
permanganate injections.
Region 2
Mannheim Avenue Dump,
NJ (OU 1)
B-9
Landfill/Dump
Soil/Groundwater
Chlorinated VOCs,
Metals (TCE, Lead)
Excavation, pump-and-
treat, MNA.
Tabernacle Drum Dump, NJ
(OU1)
B-ll
Landfill/Dump (Rural
area with a one-time
dumping of solvents,
paints, and paint sludge)
Soil/Groundwater
Chlorinated VOCs
(TCA, DCE)
Removal of drums,
excavation of soil, pump-
and-treat.
Pasley Solvents and
Chemicals, Inc., NY (OU 1)
B-13
Chemical Production
(Oil/Solvent Storage
and Distribution)
Soil/Groundwater/DNAPL (suspected)
Non-chlorinated VOCs,
Chlorinated VOCs
(DCE, TCA, DC A,
Chlorobenzene,
Toluene, Ethylbenzene,
Xylenes)
SVE, air sparging.
Region 3
Dover Air Force Base
(AFB), SS07/Area 2, South
Management Unit, DE
B-17
Military /F ederal
(Aircraft and Vehicle
Maintenance)
Groundwater/DNAPL (suspected)
Chlorinated VOCs,
Non-chlorinated VOCs
(PCE, TCE, DCE,
Vinyl Chloride,
Benzene)
ERD/Accelerated
anaerobic biodegradation,
MNA.
Letterkenny Army Depot
(Southeast Area), PA (OU
10)
B-21
Military /F ederal
(Ammunition Storage)
Groundwater
Chlorinated VOCs
(TCE, DCE, Vinyl
Chloride)
In situ biological treatment
using ERD with sodium
lactate injections, MNA.
Region 4
Gold Coast Oil Corp., FL
(OU1)
B-2 5
Waste TSD
(Oil/Solvent
Reclamation)
Groundwater/Soil/DNAPL (suspected)
Chlorinated VOCs,
Non-chlorinated VOCs
(PCE, TCE, DCE,
DCA, Methylene
Chloride, Toluene)
Excavation, pump-and-
treat, air sparging.
B-2
-------
Appendix B
Site
Page Number
Industry (Site
Type)
Media Type
Contaminant
Groups
(Contaminants
with Highest
Concentrations)
Technology
Hollingsworth Solderless
Terminal, FL (OU 1)
B-29
Manufacturing
(Solderless Terminals)
Soil/Groimdwater
Chlorinated VOCs
(TCE, cis-DCE, Vinyl
Chloride)
Excavation, pump-and-
treat, SVE, in situ
bioremediation with ERD
using potassium lactate and
bacteria injections.
Rochester Property, SC (OU
1)
B-33
Landfill/Dump
Soil/Groundwater
Chlorinated VOCs,
SVOCs, Metals (TCE,
DCE, Bis(2-
ethylhexyl)phthalate,
Manganese)
Excavation, air sparging,
ISCO using ozone
sparging.
Region 5
Tri-State Plating, IN (OU 1)
B-35
Metal Works/Plating
(Electroplating)
Soil/Groimdwater
Metals (Chromium)
Pump-and-treat,
excavation, drum removal,
decontamination and
demolition of site
buildings.
Region 6
Odessa Chromium II, TX
(OUs 1-3)
B-37
Manufacturing
(Radiator repair facility)
Groundwater
Metals (Hexavalent
Chromium)
Pump-and-treat, ISCR with
ferrous sulfate treatment.
Region 9
Del Norte County Pesticide
Storage, CA (OU 1)
B-39
Chemical Production
(Storage of pesticides)
Soil/Groundwater
Pesticides, Herbicides,
Chlorinated VOCs (1,2-
DCP, 2,4-D)
Excavation and offsite
disposal for soil, pump-
and-treat, MNA.
Firestone Tire and Rubber,
CA (OU 1)
B-43
Manufacturing (Tire)
Soil/Groundwater
Chlorinated VOCs,
Non-chlorinated VOCs
(Benzene, DCE, DCA,
PCE, Toluene, TCE,
Xylene)
Excavation and capping,
pump-and-treat.
Pemaco, CA (OU 1)
B-45
Chemical Production
(Blending and
Distribution)
Soil/Groundwater/DNAPL (suspected)
Chlorinated VOCs,
Non-chlorinated VOCs,
SVOCs, Metals, PAHs
(PCE, TCE, DCE,
Vinyl Chloride)
Excavation and off-site
disposal of soil, SVE, in
situ thermal treatment
(ERH), high-vacuum dual
phase extraction, pump-
and-treat, and MNA.
B-3
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Appendix B
Contaminant
Site
Page Number
Industry (Site
Type)
Media Type
Groups
(Contaminants
with Highest
Concentrations)
Technology
In situ thermal treatment,
Southern California Edison,
Visalia Pole Yard, CA (OU
1)
B-49
Wood Treatment
Soil/Groundwater/DNAPL
SVOCs, C SVOCs, PCP,
dioxins
(Benzo( a)pyrene,
TCDD)
enhanced in situ
bioremediation (air
sparging and bioventing),
pump-and-treat, VEB
(slurry wall), excavation.
Chlorinated VOCs,
Western Pacific Railroad
Co., CA (OU 1)
B-53
Other (Rail Facility)
Soil/Groundwater
Metals, PAHs (DCE,
DCA, TCE, Arsenic,
Lead)
Excavation, pump-and-
treat, SVE.
Region 10
Fort Lewis Logistics Center,
WA (East Gate Disposal
B-57
Military/F ederal
(Maintenance and
Soil/Groimdwater/DNAPL/LNAPL
Chlorinated VOCs,
Petroleum
Pump-and-treat, drum
removal, electrical resistive
Yard (EGDY) OU1)
Disposal Yard)
Hydrocarbons (TCE)
heating (ERH).
Notes:
(1) Not all remedies and contaminants are presented for each site.
(2) Remedies listed are specific to the media, contaminant, and operable unit that are the subject of this report.
(3) One primary site type selected for each site.
(4) Other site type includes two transformer/electrical facilities, one grain facility, one rail facility, one textile mill, one oil field one oil field services facility, and one salvage/storage yard/retail
facility.
B-4
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Appendix B
This Page Intentionally Left Blank
B-5
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Appendix B
Eastern Surplus Company Superfund Site, Southern Plume
Eastern Surplus Company Superfund Site,
Southern Plume
Site Location: Meddybemps, Washington County, ME,
Region 1
EPA ID#: MED981073711
Regulatory Agency: U.S. EPA, Maine Department of
Environmental Protection (MEDEP)
Site Summary: Remedial actions at the Eastern
Surplus Company NPL site included the cleanup of
chlorinated volatile organic compounds (VOCs),
metals, and PCBs from groundwater and soils. Key site
contaminants of concern (COCs) included
tetrachloroethene (PCE), trichloroethene (TCE),
manganese, lead, and polychlorinated biphenyls
(PCBs). MEDEP initiated several removal actions
starting in 1985, and the site was listed on the NPL in
1996. After being listed on the NPL, contaminated
surface and subsurface soils were excavated and
shipped off-site for disposal. In addition, sediment from
Dennys River contaminated with elevated
concentrations of PCBs was removed along with the
soils. Contaminated groundwater was discovered in
two separate plumes, identified as the northern and southern plumes. A combined groundwater pump-and-
treat and an in situ chemical oxidation (ISCO) remedial program were implemented at both plumes. VOC
contaminant concentrations within the southern plume have decreased to below concentration goals, which
are based on EPA maximum contaminant levels (MCL) or Maine's Maximum Exposure Guidelines (MEG),
whichever is lower for the contaminant of concern (EPA, 2011). However, the majority of the contamination
remains in the northern plume which will be addressed using enhanced in situ bioremediation.
Site History: The Eastern Surplus Company site operated
from 1946 to 1976 as a salvage and storage yard to store
and re-sell supplies, materials, and equipment from the U.S.
Department of Defense (DOD). An inspection by MEDEP in
1984 noted chemical odors, leaking electrical transformers,
hundreds of deteriorating drums and containers,
compressed gas cylinders, 16,000 pounds of calcium
carbide, and numerous areas of stained soil. The northern
portion of the site covers approximately 4-5 acres, and the
southern portion covers approximately 2-3 acres. The site is
bounded by residential properties, Meddybemps Lake, the
Dennys River, and undeveloped land. The overburden soils
consist of stratified beds of gravel, sand, and mixed sands
and silt and range from 5 to 20 feet in thickness in the
northern plume and 10 to 30 feet in the southern plume.
Depth to groundwater in the southern plume ranges from 12
to 20 feet below ground surface (bgs), while the overburden
in the northern plume is only seasonally saturated. Bedrock
at the site is a combination of Meddybemps granite with a gabbro-diorite intrusion (EPA, 1990).
The MEDEP initiated a removal action in 1985 to stabilize the site by removing approximately 120
transformers, 4,650 gallons of waste oil, and 2,400 gallons of PCB oil. In 1986, EPA took over the removal
action, which involved the inspection, evaluation, and removal of thousands of leaking drums and cans, and
Eastern Surplus NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including PCE and
TCE, metals including manganese and lead, and PCBs;
highest concentrations in groundwater included 6,700
ppb PCE (northern plume) and 1,100 ppb PCE
(southern plume)
¦ Media: Groundwater, soil, sediment, DNAPL
(suspected in northern plume), fractured bedrock
¦ Plume: Approx. 1 acre northern chlorinated VOC
plume; approx. 1.5 acre southern chlorinated VOC
plume; depths up to 20-30 feet bgs
¦ Technologies:
o Groundwater pump-arid-treat with carbon filtration
and ion exchange treatment of extracted
groundwater
o ISCO (sodium permanganate)
¦ Major Successes:
o Remediated source of soil, groundwater, and
sediment contamination within 10 years
o Southern plume groundwater contaminant
concentrations reduced to below MCLs
o Current site use includes a major archaeological
research site for the history of the Passamaquoddy
people
SHHHhB
Treatment Building (EPA, 2011)
B-6
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Appendix B
Eastern Surplus Company Superfund Site, Southern Plume
over 2,000 compressed gas cylinders (EPA, 2006). The site was listed on the NPL in June 1996, and a non-
time critical removal action (NTCRA) was completed in 1999 and 2000, The NTCRA involved soil excavation
and disposal, and the installation of a source control groundwater extraction system (EPA, 2006), The
Remedial Investigation/Feasibility Study (RI/FS) was also completed in 1999, and a record of decision
(ROD) was issued in September 2000 (EPA, 2000) which selected pump-and-treat for the two groundwater
plumes, enhancement of the system through flushing and/or ISCO to facilitate the removal of contamination,
and land use restrictions to prevent ingestion of groundwater and disturbance of archaeological resources.
Beginning in 2001, EPA enhanced the groundwater component of the ROD by implementing ISCO with
sodium permanganate. Three five-year reviews have been performed to date (EPA, 2006, 2011, and 2016)
EPA performed a bench-scale study in 2011 and a pilot study in 2012-2013 of enhanced in situ
bioremediation (EISB) in the northern plume. Based on the positive impact, EPA is preparing to expand to a
full-scale implementation of EISB.
Extent of Contamination: Two distinct groundwater VOC plumes were identified at the site, an
approximate 1 acre northern plume and an approximate 1.5 acre southern plume. PCE was detected in the
northern plume at a maximum concentration of 6,700 pg/L (ppb). Because this concentration is greater than
1 percent of PCE's solubility in water, it indicates the
possible presence of a DNAPL at this site (EPA, 1992).
Other VOCs were detected in the northern plume
above cleanup goals including TCE, cis-1,2-
dichloroethene (cis-DCE), 1,1,2-trichloroethane,
xylene, and methylene chloride. The ROD-specified
groundwater cleanup goals are based on MCLs or
Maine's MEG including 3 ppb for PCE (MEG), 5 ppb for
TCE (MCL), 70 ppb for cis-DCE (MCL), 3 ppb for 1,1,2-
trichloroethane (MEG), 600 ppb for xylene (MEG), and
5 ppb for methylene chloride (MCL). The southern
plume contained PCE at a maximum concentration of
1,100 ppb and PCBs detected at a concentration of 3
ppb. Both plumes were believed to be discharging to
the Dennys River. A majority of contamination in the
northern plume was located in fractured bedrock with
possible DNAPL, whereas the southern plume was
located in overburden and shallow bedrock.
Cleanup Approach: Remedial actions for both contaminated groundwater plumes began in 1999 as part of
the NTCRA. The northern plume groundwater extraction system came online in January 2000 and the
southern plume extraction system came online in September 2000. The interim system completed during the
NTCRA was augmented with additional extraction wells and injection wells which were used to enhance the
flushing of the plume to the extraction wells. A total of 10 extraction wells were installed in the northern
plume and six extraction wells in the southern plume. The treatment system for the extracted groundwater
consisted of filtration of suspended solids, liquid-phase granular activated carbon (GAC) for removal of
VOCs, and ion exchange to remove metals of concern. After a two-phase pilot study from July 2000 until
June 2001, a full scale ISCO application was implemented from August 2002 through January 2003 using
sodium permanganate. Sodium permanganate solution was injected in direct push wells within both plumes
with additional permanganate solution added to re-circulating wells. Results indicated that sodium
permanganate was effective in destroying dissolved PCE in bedrock in the northern plume, but needed to be
effectively delivered into the bedrock fractures to ensure adequate contact with the PCE (EPA, 2006).
Sodium permanganate injections in the southern plume indicated that PCE concentrations increased after
full scale permanganate injections (which could indicate dissolution of sorbed DNAPL), then declined for five
consecutive sampling events. The groundwater pump-and-treat system operated full-scale until January
2003, and was shut down for a short period to evaluate how contaminant concentrations would change or
rebound. The system was restarted in August 2003 after groundwater sampling data indicated that
concentrations had increased. Extraction wells located within the southern plume were shut down in late
2010 as VOC concentrations had decreased to below the cleanup goals (MCLs and MEGs) (EPA, 2011).
Extraction wells at Eastern Surplus Company
Superfund Site (EPA, 2006)
B-7
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Appendix B
Eastern Surplus Company Superfund Site, Southern Plume
Cleanup Success: The southern contaminated groundwater plume was successfully treated using a
conventional pump-and-treat system supplemented by the injection of sodium permanganate (ISCO) to
accelerate degradation of contaminants. As a result of this approach, combined with source removal during
the NTCRA, the approximately 1.5 acre southern plume was cleaned up to drinking water standards, and
extraction wells located within the southern plume were shut down in late 2010. Remediation continues,
however, within the northern plume where concentrations are still above MCLs due to the more complex
geology and higher (DNAPL range) initial concentrations in groundwater. Current site use includes a major
archaeological research site for the history of the Passamaquoddy people.
Table 1. Summary of PCE Concentration in Southern Plume at the Eastern Surplus NPL Site
Treatment Phase
PCE Maximum Concentration
(PPb)
Initial Maximum Concentration in Overburden
1,100*
Before ISCO Pilot Study
570 (overburden)*
200 (bedrock)*
After ISCO Pilot Study (July 200 -June 2001)
160 (overburden)
77 (bedrock)
After Full-Scale ISCO (August 2002- January 2003)
25 (overburden)*
22 (bedrock)*
April 2006
9 (overburden)*
6 (bedrock)*
Current Maximum Concentration
Below MCL and MEG**
Sources: * EPA, 2006 and ** EPA, 2011
ppb = parts per billion
References
United States Environmental Protection Agency; Third Five Year Review. Eastern Surplus Company
Superfund Site, Washington County, Maine. September 28, 2016.
United States Environmental Protection Agency Web site; Superfund Site Profile; 2011.
United States Environmental Protection Agency; Second Five Year Review. Eastern Surplus Company
Superfund Site, Meddybemps, Maine. September 29, 2011.
United States Environmental Protection Agency; Five Year Review. Eastern Surplus Company Superfund
Site, Meddybemps, Maine. September 29, 2006.
United States Environmental Protection Agency; Record of Decision. Eastern Surplus Company Superfund
Site, September 28, 2000.
United States Environmental Protection Agency. Estimating Potential for Occurrence of DNAPL at
Superfund Sites. OSWER Publication 9355.4-07FS. January 1992.
B-8
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Appendix B
Mannheim Avenue Dump NPL Site
Mannheim Avenue Dump NPL Site
Site Location: Galloway Township, NJ, Region 2
EPA ID#: NJD980654180
Regulatory Agency: U.S. EPA, New Jersey
Department of Environmental Protection (NJDEP)
Site Summary: Remedial actions at the Mannheim
Avenue Dump NPL site included cleanup of lead and
trichloroethene (TCE) in soil and TCE in groundwater.
The soil remedy included the excavation and off-site
incineration of contaminated soil (EPA, 1990).
Groundwater cleanup involved a pump-and-treat
groundwater system with air stripping of extracted
groundwater for 18 months (EPA, 1999). Pump-and-
treat was followed by monitored natural attenuation
(MNA). The cleanup level of 1 |jg/L (ppb) for TCE in
groundwater was met by 2002 (EPA, 2004). The site
was deleted from the NPL in 2007 (EPA, 2010).
Site History: The Mannheim Avenue Dump was a sand and gravel pit, which ceased operation in 1964.
Beginning in 1964, the site was used by Lenox China to dispose of industrial wastes from manufacturing and
by Galloway Township to dispose of municipal wastes. The aquifer underlying the site consists of shallow
and deep zones, each comprised of sand and gravel, separated by an approximately 3-to-5-foot thick semi-
permeable clay layer. The depth to shallow groundwater is approximately 35 feet below ground surface
(bgs). Groundwater flows in a northwesterly direction in the shallow zone and in a northeasterly direction in
the deeper zone (EPA, 2004).
In 1981, an industrial survey report from Lenox China notified the NJDEP that hazardous waste could have
been disposed of on-site, including 55-gallon drums of TCE degreasing sludge. A subsequent NJDEP
investigation revealed the presence of exposed 55-gallon drums in deteriorating conditions. Drum samples
were collected and indicated the presence of VOCs and heavy metals. The site was placed on the NPL in
1983. Sludge and soil removal actions began in 1985, and a Remedial Investigation/Feasibility Study
(RI/FS) and a record of decision (ROD) were completed in 1990 (EPA, 1990). The groundwater remedy
began in 1994 and in eight years, TCE concentrations in all wells were below the NJDEP Drinking Water
Standard cleanup level of 1 ppb (EPA, 2004). The second five-year review was completed in 2004 (EPA,
2004) and the site was deleted from the NPL in 2007 (EPA, 2010).
Extent of Contamination: The highest concentration of lead in soil was 48,000 ppm (EPA, 1999). The
highest concentration of TCE in sludge was 2,000 ppm (ATSDR, 1993). TCE contamination was detected in
both the shallow and deep aquifer zones. Initial TCE concentrations of 140 ppb in groundwater were found
onsite after initial cleanup efforts. Following the sludge and soil removal actions, TCE was still detected at
concentrations up to 29 ppb and 47 ppb in the shallow and deep aquifers, respectively. The TCE plume in
excess of 1 ppb in the shallow aquifer zone was estimated to be 100 feet long, 400 feet wide, and 15 feet
deep, while the plume in the deep aquifer zone was estimated to be 1,000 feet long, 1,000 feet wide, and 55
feet deep (EPA, 1990).
Cleanup Approach: In 1985, initial cleanup of the site involved the removal of 25,000 pounds of degreasing
sludge and treatment of the sludge using off-site incineration. In 1989, 2,700 cubic yards (CY) of lead-
contaminated soil from 35 soil piles was excavated and incinerated off-site (EPA, 2010). The groundwater
remedy involved a pump-and-treat system consisting of three extraction wells, one screened in the shallow
aquifer and two screened in the deep aquifer. The contaminated groundwater was pumped to the treatment
system at a rate of 40 gallons per minute (gpm) where VOCs were removed using air stripping. The treated
groundwater was then re-injected into the aquifer. The treatment system operated for 18 months from
Mannheim Avenue Dump NPL Site
Remediation Highlights
¦ Contaminants: TCE in groundwater and TCE and lead
in soil; highest concentration in groundwater was 140
ppb TCE.
¦ Media: Groundwater, Soil
¦ Plume: TCE in groundwater covered an area of 1,000
feet by 1,000 feet and extended 55 feet deep
¦ Technologies:
o Drum, sludge, and soil removal
o Groundwater pump-and-treat with air stripping
treatment
o MNA
¦ Major Success:
o Over 25,000 pounds of contaminated sludge and
2,700 cubic yards of contaminated soil removed
o Remedy met stringent NJDEP cleanup level of 1
ppb for TCE in approximately eight years of
combined pump-and-treat and MNA
B-9
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Appendix B
Mannheim Avenue Dump NPL Site
August 1994 to April 1996, when it was determined thatTCE concentrations in the influent had dropped
below the 1 ppb cleanup level. The pump-and-treat system was shut down, and was followed by MNA. A
total of 30 million gallons of contaminated groundwater were treated during pump-and-treat system
operation (EPA, 2010). Long term monitoring data indicated thatTCE concentrations in the 32 monitoring
wells were steadily declining, and had reached levels lower than the NJDEP Drinking Water Standard
cleanup level of 1 ppb in all but two wells. MNA continued since the TCE concentration in one well remained
as high as 22 ppb. By 1999, only one well had a concentration above cleanup levels, at around 4 ppb (EPA,
1999). Monitoring data demonstrated that all well concentrations were below the cleanup level by 2002, and
remained so through 2003 (EPA, 2004). Table 1 demonstrates the reduction in the maximum TCE
concentrations in groundwater at the site as a result of the implemented remedy.
Cleanup Success: The cleanup at the Mannheim Avenue Dump NPL site incorporated two large
contaminant source area removals, followed by pump-and-treat and MNA of groundwater. The source
removals helped to expedite the cleanup of the groundwater. After operating the pump-and-treat system for
only 18 months, followed by approximately six years of MNA, the sizable TCE plumes in both the shallow
and deep aquifer zones were remediated to below the NJDEP cleanup levels. The site was deleted from the
NPL in 2007.
Table 1. Concentration Reduction in Groundwater at the Mannheim Avenue Dump NPL Site
Timeframe
Maximum TCE Concentration (ppb)
Investigations in 1985/1986
140*
Investigations for RI/FS 1989/1990; After Removal Actions
47*
After 18 Month of Pump-and-Treat System Operation 1996
22**
After ~ 3 Years of MNA 1999
4«
After Another 3 Years of MNA 2002
Source: * = EPA, 1990; ** = EPA, 1999; * * * = EPA, 2004
ppb = parts per billion
References
Agency for Toxic Substances and Disease Registry; Public Health Assessment for Mannheim Avenue
Dump. Galloway Township, Atlantic County, New Jersey; November 5, 1993.
United States Environmental Protection Agency, Region 2; Mannheim Avenue Dump Site Profile; 2010.
United States Environmental Protection Agency; Second Five-Year Review for Mannheim Avenue Dump
Site; 2004.
United States Environmental Protection Agency; Five-Year Review Report. Mannheim Avenue Dump
Superfund Site; 1999.
United States Environmental Protection Agency; EPA Superfund Record of Decision: Mannheim Avenue
Dump; 1990.
B-10
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Appendix B
Tabernacle Drum Dump NPL Site
Tabernacle Drum Dump NPL Site
Site Location: Tabernacle Township, NJ, Region 2
EPA ID#: NJD980761357
Regulatory Agency: U.S. EPA, New Jersey
Department of Environmental Protection (NJDEP),
Burlington County Health Department (BCHD)
Site Summary: Remedial actions at the Tabernacle
Drum Dump NPL site were handled in two stages. A
time critical removal action was conducted to remove
leaking storage containers holding waste paint, paint
sludge, and solvents and the resulting contaminated
soil. A subsequent long-term remedial phase focused
on cleanup of groundwater using a pump-and-treat
system with air stripping to remove chlorinated volatile
organic compounds (VOCs) from the extracted
groundwater. Key contaminants of concern in
groundwater included 1,1,1-trichloroethane (1,1,1-TCA)
and its breakdown product, 1,1-dichloroethene (1,1-
DCE). The pump-and-treat system was successful in reducing contaminant levels forTCA and 1,1-DCE to
below their NJDEP maximum contaminant levels (MCLs) in just over four years (EPA, 2010).
Site History: The Tabernacle Drum Dump was a 1-acre wooded site which was used by Atlantic Disposal
Services (ADS) to illegally dispose of approximately 200 containers of waste solvent, paint, and paint sludge
on an approximately 2,000-square-foot portion of the property in 1976 or 1977. Two aquifers exist beneath
the site, separated by an intermittent, 20-foot thick clay layer. The upper water-bearing source is the
Cohansey aquifer, which consists of up to approximately 100 feet of highly permeable soils, and supplies the
majority of residents living in the vicinity. In some areas, the Cohansey aquifer is hydraulically connected to
the underlying Kirkwood aquifer, which is not typically used as a source of potable water. The direction of
groundwater flow is southeasterly, and the principal threat posed at the site was the potential ingestion of
groundwater by down gradient residents (EPA, 1988).
The containers were discovered by the Tabernacle Township in 1982. In 1984, EPA issued an
administrative order to ADS to perform an emergency removal action of waste containers, drummed
materials, contaminated soil, and liquid materials. In September 1984, the site was finalized for inclusion on
the NPL. EPA completed a Remedial Investigation/Feasibility Study (RI/FS) and signed a record of decision
(ROD) in 1988. Installation of a groundwater pump-and-treat system was completed in July 1993 and
operated until 1997, when cleanup levels were achieved. The site was deleted from the NPL in May 2008
(EPA, 2010).
Extent of Contamination: The area of surface contamination covered approximately 2,000 square feet of
the 1-acre site. Initial maximum concentrations of 1,1,1-TCA and 1,1-DCE in groundwater were 1,000 |jg/L
(ppb) and 180 ppb, respectively, with concentrations of 1,1,1-TCA significantly exceeding the NJDEP MCL
of 26 ppb in six of the eight wells on the site (EPA, 1988). The plume extended 3,000 feet southeast of the
original dump location (EPA, 2010). The maximum initial concentration detected in groundwater and
concentration ranges during post-remedial monitoring are shown in Table 1.
Cleanup Approach: The initial remedial action at the Tabernacle Drum Dump NPL site was conducted by
ADS in 1984, under the supervision of EPA, and consisted of surface cleanup. This action included removal
and off-site disposal at a hazardous waste facility of 40 cubic yards (CY) of drummed material, eight
truckloads of excavated soil, and approximately 3,000 gallons of liquid material (EPA, 2010). The RI/FS
completed by EPA in 1988 showed that the contaminant plume was migrating to the southeast of the original
dump location in the direction of residential drinking water wells, and a ROD was signed later that year. A
Tabernacle Drum Dump
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including 1,1,1 -TCA
and breakdown product 1,1-DCE; highest
concentrations in groundwater included 1,000 ppb
1,1,1-TCA and 180 ppb 1,1-DCE
¦ Media: Groundwater, Soil
¦ Plume: VOCs in groundwater extended approximately
3,000 feet from the source location
¦ Technologies:
o Emergency removal action to remove damaged and
leaking drums and affected soil
o Groundwater pump-and-treat system with air
stripping to treat extracted groundwater
¦ Major Successes
o Soil contaminant concentrations below cleanup
levels after emergency action
o 1,1,1 -TCA concentrations reduced from 1,000 ppb
to below NJDEP cleanup level of 26 ppb
o Groundwater cleanup levels achieved with just over
four years of pump-and-treat
B-11
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Appendix B
Tabernacle Drum Dump NPL Site
groundwater pump-and-treat system was constructed and
began operation in 1993. The system pumped
groundwater, treated it with air stripping to remove VOCs,
and re-injected it into the aquifer at a rate of
approximately seven million gallons per month (EPA,
2010). Quarterly groundwater sampling that began in
October 1993 and continued throughout the program
showed decreasing concentrations of contaminants. In
December 1997, the pump-and-treat system was shut
down, as EPA concluded contaminant concentrations had
decreased below cleanup levels (EPA, 1998). Five years
of post-remediation monitoring 1999-2005) verified that
the RAOs and cleanup levels were met. In 2005, the
pump-and-treat system was dismantled and monitoring
wells were abandoned. The site was deleted from the
NPL in May 2008 (EPA, 2010).
Cleanup Success: The Tabernacle Drum Dump NPL site
was successfully remediated using a combination of a time-critical source removal of leaking drums and
contaminated soil with a subsequent pump-and-treat groundwater remedy. Groundwater cleanup levels
were met in just over four years of pump-and-treat operation. The pump-and-treat system reduced 1,1,1-
TCA concentrations from 1,000 ppb to less than 2 ppb, and 1,1 -DCE concentrations from 180 ppb to less
than 1 ppb. Five years of post-remediation monitoring verified that cleanup levels were met and the site was
deleted from the NPL in 2008 (EPA, 2010).
Table 1. Pre- and Post-Remediation Contaminant Concentrations in Groundwater
Contaminant of Concern
Initial Maximum
Concentration (ppb) -
July 1985
Remedial Goal (ppb)
(NJDEP MCL)
Concentration Ranges
During Monitoring
(1996-1997)
1.1.1 -T richloroethane
1,000
26
0.5-2.0
1,1 -Dichloroethene
180
2
0.2-1.0
Source: EPA, 1998
NJDEP = New Jersey Department of Environmental Protection
MCL = Maximum Contaminant Level
ppb = parts per billion
References
United States Environmental Protection Agency, Region 2; Site Overview. Tabernacle Drum Dump; 2010.
United States Environmental Protection Agency, Region 2; Five -Year Review (Type I). Tabernacle Drum
Dump Site; 1998.
United States Environmental Protection Agency; Superfund Record of Decision: Tabernacle Drum Dump.
1988.
Waste Technology, Inc.; Biannual Inspection Report for the Tabernacle Drum Dump Site. August 10, 1999.
Treatment building and air stripper tower (Waste
Technology, 1999)
B-12
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Appendix B
Pasley Solvents and Chemical NPL Site
Pasley Solvents and Chemical NPL Site
Site Location: Hempstead, NY, Region 2
EPA ID#: NYD991292004
Regulatory Agency: U.S. EPA, New York State
Department of Environmental Conservation (NYSDEC),
Nassau County Department of Health (NCDH)
Site Summary: Remedial actions at the Pasley
Solvents and Chemical NPL site included the cleanup
of halogenated and non-halogenated volatile organic
compounds (VOCs) from groundwater and soil. Key
contaminants included chlorobenzene, 1,1-
dichloroethane (1,1-DCA), 1,1-dichloroethene (1,1-
DCE), frans-1,2-dichloroethene (frans-1,2-DCE), 1,1,1-
trichloroethane (1,1,1-TCA), toluene, ethylbenzene,
and xylenes. The remedy included in situ treatment of
groundwater and soil using air sparging (AS) and soil
vapor extraction (SVE). All cleanup levels were met
within five years after completing construction of the
remedy (EPA, 2009a).
Site History: The Pasley Solvents and Chemical
Company is a former tank farm that stored and distributed oil, solvents, and other chemicals. The facility
operated from 1969 to 1982. Leaking tanks contaminated soil and groundwater at the site. There are two
distinct geological/hydrological formations at the site, the Upper Glacial aquifer and the Magothy aquifer.
The Upper Glacial aquifer consists of up to 60 feet of unconsolidated sand and gravel, while the Magothy
formation consists of up to 400 to 500 feet of thick fine sands with thin, discontinuous layers of silt and clay.
The groundwater in these aquifers flows in a south to southwesterly direction, depending upon depth (EPA,
2009a). In 1980, inspection by the NCDH revealed soils contaminated with VOCs (EPA, 2009a). In 1981,
the company had five groundwater monitoring wells installed, and groundwater samples indicated the
presence of VOCs, including benzene, tetrachloroethene (PCE), toluene, and xylene, above State Drinking
Water Standards (EPA, 1992). In 1982, operations at the site ceased, and it was placed on the NPL in 1986.
Removal of the tank farm was conducted in 1988, a Remedial Investigation and Feasibility Study (RI/FS)
was completed, and a record of decision (ROD) was issued in 1992. The ROD selected remediation of
groundwater by extraction, treatment, and recharge of the treated groundwater into the aquifer, and SVE to
treat contaminated soils. A ROD Amendment was issued in 1995 to allow groundwater treatment via in situ
AS instead of constructing the original ROD-selected treatment system. Remedial construction was
completed and the system became operational in November 1997. The system operated for five years, and
was followed by post-remediation monitoring demonstrating all remedial action objectives (RAOs) had been
met. The final Close Out Report was signed in 2005 (EPA, 2009a). The site was deleted in September of
2011.
Extent of Contamination: The highest concentration of total VOCs detected in surface soil was 603,000
|jg/L (ppb). VOCs detected in soil at 6 to 12 inches below ground surface (bgs) were also generally present
in the groundwater. Trans-1,2-DCE concentrations, the most prevalent contaminant in groundwater at the
site, were as high as 37,000 ppb (EPA, 2009b). The groundwater plume was located in the Upper Glacial
aquifer at depths up to 60 feet bgs, and extended to the southwest for approximately 400 feet (EPA, 1992).
Contamination detected in a cluster of up gradient wells indicated that contamination was entering the site
from the adjacent Roosevelt Field Superfund site. Because the Roosevelt Field site was suspected to be
contributing TCE and PCE to the upper aquifer, the up gradient well cluster was not used to define the
plume for the site. The sum of these VOCs was labeled as total volatile organic index compounds (TVOICs)
and included chlorobenzene, 1,1-DCA, 1,1-DCE, ethylbenzene, toluene, trans-1,2-DCE, 1,1,1-TCA, and
Pasley Solvents and Chemical NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including
chlorobenzene, 1,1-DCA, 1,1-DCE, frans-1,2-DCE, and
1,1,1-TCA, and VOCs including toluene, ethylbenzene,
and xylenes; highest concentrations in groundwater
included 37,000 ppb frans-1,2-DCE
¦ Media: Groundwater, Soil
¦ Plume: Groundwater DCE plume extended
approximately 400 feet southwest of the source and
reached depths of 60 feet
¦ Technologies:
o SVE
o AS
¦ Major Success:
o Large reduction of total volatile organic index
compounds in groundwater in first two years (from
37,000 ppb to 4 ppb)
o Over 15,000 pounds of contaminants removed from
soil and groundwater
o Cleanup levels achieved within five years of
AS/SVE system startup
o Deleted from the N PL i n 2011
B-13
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Appendix B
Pasley Solvents and Chemical NPL Site
xylenes (EPA, 1992). The TVOIC compounds were found to contribute a major part (88 percent) of the
contamination found in the monitoring well cluster located on-site. TCE and PCE are not considered to have
originated at the site and are not TVOIC compounds. Maximum concentrations of TCE and PCE were
detected at 320 ppb and 27 ppb, respectively. The use of index compounds allowed identification of a well-
defined contaminant plume for the site (EPA, 1992).
Cleanup Approach: Initial cleanup of the site involved the removal of the tank farm in 1988, followed by the
removal of contaminants from water and soil using AS and SVE, respectively. For the groundwater remedy,
a total of 34 2-inch AS wells were installed and screened at 50 to 52 feet, both on-site and off-site. For SVE,
13 2-inch wells and eight 4-inch wells were placed in contaminant source areas, and were screened at either
5 to 10 feet or 15 to 20 feet. The collected vapors were treated with activated carbon. The AS/SVE system
construction was completed and started operating in 1997. It operated for five years (1997-2002) as
required by a Consent Decree (EPA, 2009b). There were four onsite monitoring wells that were monitored
during the remedy, with 19 rounds of samples collected on a semi-annual basis (EPA, 2009a). These
samples showed TVOIC concentrations in three wells had been reduced non-detectable levels after only two
years of treatment (EPA, 2009b). The fourth well, MW-2S, required five years of treatment and the
implementation of contingency measures before the TVOICs (specifically xylene) were reduced below the
cleanup levels. Contingency measures included shutting off the east side air sparging wells and diverting air
to the area around MW-2S, installing two more AS wells near MW-2S, and adding inorganic nutrients (in the
form of a commercial garden fertilizer) to the west side well in an attempt to accelerate biological activity for
further chemical reduction. Table 1 lists the pre-remediation and post-remediation TVOIC concentrations
from the on-site monitoring well MW-2S. All individual TVOICs were below their cleanup levels at shutdown
of the system in 2002 and during subsequent rounds of monitoring (EPA, 2009a). Both soil and groundwater
cleanup objectives were met within five years of the start of the AS/SVE treatment (EPA, 2009a), removing
approximately 15,461 pounds of contaminants from the site.
Cleanup Success: The Pasley Solvents and Chemical NPL site was treated for both soil and groundwater
contamination. An AS/SVE system was operated on-site and off-site for five years, reducing TVOICs in
groundwater and contaminants in soil below cleanup levels. The SVE system reduced soil contamination
over a period of five years, while the AS system reduced very high TVOIC concentrations in groundwater
from 37,000 ppb before remediation to 4 ppb within only two years (EPA, 2009a). The completed
remediation of the site allowed for beneficial reuse. The Metropolitan Transit Authority (MTA) leased the
property and currently uses it for a police station (EPA, 2009c). The site was deleted from the NPL in 2011.
Table 1: Reduction in TVOIC Concentrations in Upper Aquifer Groundwater Monitoring Well MS-2S -
Pasley Solvents and Chemical NPL Site
Chemical
Onsite Monitoring Well
MW-2S
Federal Drinking
Water Standard
March 1990* (ppb)
August 2005** (ppb)
(ppb)
Chloroform
33
ND
NS
1,1 -Dichloroethene
62
ND
7
1,1 -Dichloroethane
300
2J
NS
trans-l,2-Dichloroethene
25,000
ND
100
1,1,1 -T richloroethane
3,600
2J
200
Ethylbenzene
510
ND
700
Toluene
1,100
ND
1,000
Chlorobenzene
510
ND
100
Xylene
1,100
ND
10,000
* Source: EPA, 1992, ** Source: EPA, 2009a; ppb = parts per billion, ND = Non-detect; NS = No Standard
B-14
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Appendix B
Pasley Solvents and Chemical NPL Site
References
United States Environmental Protection Agency; Pasley Solvents & Chemicals. Inc. Superfund Final Close-
Qut Report; 2011
United States Environmental Protection Agency; Second Five-Year Review Report. Pasley Solvents and
Chemicals Site; 2009a
United States Environmental Protection Agency; DNAPL Remediation: Selected Projects Where Regulatory
Closure Goals Have Been Achieved; pps. 47-48; 2009b.
United States Environmental Protection Agency, Region 2; Site Overview, Pasley Solvents and Chemicals,
Inc.; 2009c
United States Environmental Protection Agency, Region 2; Site Fact Sheet, Pasley Solvents and Chemicals;
2002.
United States Environmental Protection Agency; Superfund Record of Decision: Pasley Solvents &
Chemical, NY; 1992
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Appendix B
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B-16
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Appendix B
Dover Air Force Base (AFB), SS07/Area 2, South Management Unit, NFL Site
Dover Air Force Base (AFB), SS07/Area 2,
South Management Unit, NPL Site
Site Location: Dover, DE, Region 3
EPA ID#: DE8570024010
Regulatory Agency: U.S. EPA, State of Delaware
Department of Natural Resources and Environmental
Control (DNREC)
Site Summary: Remedial actions at the South
Management Unit SSQ7/Area 2 site at the Dover AFB
included the cleanup of petroleum and chlorinated
solvents in groundwater from historic aircraft
maintenance activities. Key contaminants of concern
include tetrachloroethene (PCE), trichloroethene
(TCE), c/s-1,2-dichlorethene (cis- 1,2-DCE), and vinyl
chloride in groundwater. Remedial actions included
the injection of a combination of slow-release
(emulsified vegetable oil) and soluble (sodium lactate)
substrates to achieve enhanced reductive
dechlorination (ERD) and induce accelerated
anaerobic biodegradation (AAB) to treat source area
groundwater contamination. Monitored natural
attenuation (MNA) was used to address the remainder
of the chlorinated solvent plume. A record of decision
(ROD) was signed in December 2005, and by the end
of March 2006, over 100,000 gallons of carbon
substrate-amended water had been injected into the
source area subsurface through 49 injection points,
resulting in favorable conditions for reductive
dechlorination. ERD resulted in meeting remediation
standards in most SS07 source area wells within 2
years. By 2008 nearly all wells met the groundwater
remediation standards established in the 2005 ROD
were the federal maximum contaminant levels (MCLs)
of 5 ppb for PCE and TCE. In 2014 the Air Force
revised the remediation standards to be the State of
Delaware MCLs of 1 pg/L (ppb) for PCE, TCE, and vinyl
chloride (USAF, 2014). The most recent available semi-annual monitoring data (January 2016) indicated
exceedances in 2 source area wells. In one well TCE, c/s-1,2-DCE and vinyl chloride were 86 ppb, 840 ppb
and 130 ppb, respectively. At the other well TCE and vinyl chloride were 23 ppb and 8 2ppb, respectively.
These wells are being resampled to confirm concentrations. (USAF, 2013, USAF, 2016).
Site History: Dover AFB was listed on the NPL in March 198S and contains 20 OUs, each with a
corresponding ROD. As part of the overall site cleanup strategy for the Base, Dover AFB was divided into
four management units for the purpose of conducting remedial investigations and feasibility studies. OU15,
also known as the South Management Unit (SMU), contains the SS07/Area 2 site and three additional sites.
The three additional sites include LF17 (a former landfill used for disposal of general refuse), FT01 (a former
fire training area), and LF18 (a former landfill used for disposal of general refuse and industrial shop waste).
The ROD selected remedies for these three additional sites included MNA with periodic monitoring and land
use controls (LUCs). These three additional areas are not the focus of this Site Summary, and will not be
discussed further.
Dover Air Force Base, South Management Unit, NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including PCE. TCE,
c/s-1,2-DCE, and vinyl chloride; highest concentrations in
groundwater included 32,000 ppb PCE and 110 ppb TCE
¦ Media: Groundwater, DNAPL
¦ Plume Size: Chlorinated VOC groundwater plume
approximately 2,800 feet long by 650 feet wide
¦ Technologies:
o ERD
Q AAB
o Natural attenuation
¦ Major Successes:
o Injection of over 100,000 gallons of carbon substrate
into subsurface
o ERD reduced contaminants of concern in most source
area wells to below cleanup levels within two years
o Natural attenuation is effectively lowering contaminant
concentrations in adjacent plumes
o Off-site migration of contaminated groundwater
prevented, MCLs achieved in groundwater at the
Base property line
I
SS07 at Dover Air Force Base (USAF, 2008)
B-17
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Appendix B
Dover Air Force Base (AFB), SS07/Area 2, South Management Unit, NFL Site
The SS07/Area 2 site was used as a hazardous waste storage area since 1981 and industrial activities were
conducted there since the 1940s. Although there were no documented releases of contaminants at SS07,
signs of surface spills were evident during remedial investigations of the site, and solvents that were
historically used in aircraft maintenance activities and petroleum were the primary contaminants within the
Area 2 groundwater plume (USAF, 2006). SS07 is the primary source of contaminants that form the Area 2
groundwater plume. A ROD was signed in December 2005, and five-year-reviews were performed in 2008
and 2013 stating that the remedy performed at SS07/Area 2 was protective of human health and the
environment (USAF, 2008 and 2013).
Extent of Contamination: Chlorinated solvents were present in shallow groundwater from a source area
(SS07), which is part of the OU 15 SMU of the Dover AFB. The Columbia aquifer at the site is not a source
of drinking water; however, the potential existed for contaminant constituents to migrate off base, where the
aquifer is a potential drinking water source. MCL exceedances of chlorinated solvents in groundwater, which
triggered the need for remedial action, formed a long, narrow plume referred to as Area 2. The Area 2
chlorinated solvent plume extended from the SS07 source area approximately 2,800 feet down gradient.
Elevated PCE and TCE concentrations (32,000 and 110 ppb, respectively) were discovered in shallow
groundwater, approximately 10 to 15 feet below ground surface (bgs). The site has four aquifers beneath it
with varying compositions including mixtures of gravel, sand, and silt with clay and gravel lenses (USAF,
2008).
Cleanup Approach: Remedial actions began in 2005 with monitoring to determine if any undefined source
areas were located up gradient of the SS07/Area 2 plume, and to provide information for the design and
optimal location for injecting ERD substrate, including the feasibility of using permanently installed
injection/extraction wells to deliver the substrate into the subsurface. It was determined that the subsurface
formation did not have the permeability necessary for permanent injection wells. In March 2006, a
combination of slow-release (emulsified vegetable oil) and soluble (sodium lactate) substrates and nutrients
(dibasic ammonium phosphate [DAP]) were added to potable water at a ratio of 50/50 and injected into the
subsurface to stimulate the biodegradation of chlorinated solvents. Approximately 2,100 gallons of amended
water was injected into each direct-push borehole at four separate depth intervals between approximately 5
and 25 feet bgs. Injections occurred at 49 locations
within the source area, with a total of approximately
103,000 gallons of amended water injected for the
entire SS07 site. Additional monitoring wells were
installed to expand the existing well network to
monitor the effectiveness of the ERD remedy. The
entire SS07/Area 2 plume was monitored to assess
the progress of natural attenuation in reducing
contaminant concentrations. Based on delineation
sampling for a suspected source area, in July and
August 2012 additional injections were conducted
up gradient of the single well where contaminant
concentrations remained above MCLs. Twenty
temporary wells at depths ranging between 5 and
25 feet bgs were injected with 139,000 gallons of
water amended with 825 gallons of sodium lactate
and 2,000 gallons of emulsified vegetable oil.
Cleanup Success: The SS07/Area 2 groundwater contamination was treated using an innovative ERD
method to stimulate the biodegradation of chlorinated solvents. Dramatic decreases in contaminant
concentrations have been documented in semi-annual sampling programs. Since the AAB injections in
2006, concentrations of both PCE and TCE have decreased three to four orders of magnitude, and since
April 2007, neither PCE, TCE, nor breakdown products (c/s-1,2-DCE and vinyl chloride) have exceeded the
MCLs in any SS07 source area wells (USAF, 2011). Reducing conditions are stable in the source area and
the presence of ethane in several wells within and just down gradient of the source area indicates that
complete dechlorination is occurring (USAF, 2011). ERD resulted in meeting remedial standards in most
ironex
F.imronmi'nlal Fit-Id Services
1-800-VIRON E X
Injection/Extraction Well Remediation
(EPA, 2011)
B-18
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Appendix B
Dover Air Force Base (AFB), SS07/Area 2, South Management Unit, NPL Site
SS07 source area wells within 2 years. By 2008 nearly all wells met cleanup levels. In 2014 the Air Force
revised the remediation standards to be the State of Delaware MCLs of 1 ppb for PCE, TCE, and VC
(USAF, 2014). The most recent available semi-annual monitoring data (January 2016) indicated
exceedances in 2 source area wells. In one well TCE, cis-1,2-DCE and vinyl chloride were 86 ppb, 840 ppb
and 130 ppb, respectively. At the other well TCE and vinyl chloride were 23 ppb and 8.2 ppb, respectively.
These wells are being resampled to confirm concentrations. (USAF, 2013; USAF, 2016).
References
United States Department of the Air Force; Dover AFB Sampling Summary Report SS07. 2016.
United States Department of the Air Force; Monitoring Report Sites SS07, LF17, and LF18 South
Management Unit (through December 2014). March 2015.
United States Department of the Air Force; Explanation of Significant Differences for Records of Decision for
FT03, LF13, WP14/LF15, South Management Unit, Area 5, Area 6, SS08 and LF25. August 2014.
United States Department of the Air Force; Monitoring Report Sites SS07, LF17, and LF18 South
Management Unit (through October 2010), Dover Air Force Base. February 2011.
United States Department of the Air Force; Interim Remedial Action Completion Report. Sites LF17, SS07,
FT01, and LF18, South Management Unit (SMU), Dover Air Force Base. August 2006.
United States Department of the Air Force; Five-Year Review Report for Dover AFB. SS07/Area2, South
Management Unit. Sept 2013.
United States Environmental Protection Agency; Superfund Site Progress Profile Dover Air Force Base.
April 2011.
United States Environmental Protection Agency; DNAPL Remediation: Selected Projects Where Regulatory
Closure Goals Have Been Achieved. EPA 542/R-09/008. August 2009.
United States Department of the Air Force; Basewide Five-Year Reviews Dover Air Force Base, Volume II.
October 2008.
United States Department of the Air Force; Record of Decision: Dover Air Force Base OU15.
EPA/ROD/R03-06/011. 2006.
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Appendix B
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B-20
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Appendix B
Letterkenny Army Depot Southeast Area NPL Site, OU 10
Letterkenny Army Depot Southeast Area NPL
Site, OU 10
Site Location: Chambersburg, PA, Region 3
EPA ID#: PA6213820503
Regulatory Agency: US EPA
Site Summary: Remedial actions at the Letterkenny
Army Depot Southeast Area NPL site at OU 10
included the cleanup of chlorinated volatile organic
compounds (VOCs) from a leaking industrial
wastewater sewer and non-chlorinated VOCs from a
leaking underground storage tank return line. Key
contaminants of concern include trichloroethene (TCE),
frans-1,2-dichloroethene (frans-1,2-DCE), 1,1-
dichloroethene (1,1-DCE), vinyl chloride, and benzene.
The remedial action at OU 10 included in situ enhanced
reductive dechlorination (ERD) using injections of a
sodium lactate solution. In addition, monitored natural
attenuation (MNA) and land use controls were put in
place during the remedial activities. The site has not yet
been deleted from the NPL, however significant progress
Site History: The Letterkenny Army Depot began operating in 1942 for ammunition storage. In 1947, the
Army expanded operations to include testing, maintenance, and overhaul of military vehicles and missiles,
as well as the storage and transportation of industrial chemicals. These operations consisted of cleaning,
stripping, painting, lubrication, and plating activities, which involved the use of solvents, blast media (such as
sand from sandblasting operations), paints, petroleum products, and metals. The site was later included in
the 1995 Base Realignment and Closure Act (BRAC), which designates land for transfer to the private
sector for local redevelopment. Contamination at the site was first detected in 1983 in the southeast area of
the site. VOCs and metals were detected in at least six major areas, including contaminated soil, surface
water, and groundwater. At OU 10, VOC-laden wastewater associated with solvent-use stations inside
Building 37 leaked through breaks in a deteriorated industrial wastewater sewer, causing groundwater
contamination (USAEC, 2006). The contaminated aquifer that lies beneath OU-10 consists of fractured and
weathered karstic bedrock, with large cavities formed by dissolution of limestone rock. Groundwater flows in
a general east-southeast direction; however the karst nature of the aquifer makes it difficult to predict
localized flow direction and migration of contaminants (USAEC, 2006). The Letterkenny Army Depot
Southeast Area NPL site was listed on the NPL in July 1987. A record of decision (ROD) for OU 10 was
signed in September 2006, which included institutional controls. Four site-wide five-year reviews have been
completed in 2001, 2008, 2015, and 2017. An explanation of significant difference (ESD) was signed in
September 2009, which included lifting groundwater use restrictions across most of the OU 10 area (EPA,
2011).
Extent of Contamination: Dissolved phase contaminants (TCE and breakdown products) were present in
the karst aquifer and eventually migrated off-site to residential areas, and to springs located approximately
1.5 to 2.0 miles off-site (USAEC, 2006). Maximum initial onsite groundwater contaminant concentrations in
1994 for TCE, trans- 1,2-DCE, 1,1-DCE, and vinyl chloride were 200 |jg/L (ppb), 59 ppb, 13 ppb, and 90 ppb,
respectively (Table 1). Sampling of off-site wells and springs between 1991 and 1996 identified VOC
concentrations in excess of EPA maximum contaminant levels (MCLs) for groundwater and Pennsylvania
Water Quality Criteria (WQC) for springs. The primary VOCs detected in off-site wells were TCE (up to 13.9
ppb) and 1,1-DCE (up to 16.2 ppb). The primary VOCs detected in off-site springs were TCE (up to 6.4 ppb),
trans- 1,2-DCE (up to 5 ppb), and 1,1-DCE (up to 4.5 ppb) (USAEC, 2009). From the early 1980s through
1992, the Army installed alternate potable water supplies at a number of offsite residences where OU 10
Letterkenny Army Depot Southeast Area NPL Site,
OU10
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including TCE,
frans-1,2-DCE, and vinyl chloride; highest
concentrations in groundwater included 200 ppb TCE,
59 ppb,
-------
Appendix B
Letterkenny Army Depot Southeast Area NPL Site, OU 10
site-related VOC contamination had reached domestic supply wells at concentrations exceeding MCLs
(USAEC, 2006).
Cleanup Approach: The first remedial activities at OU 10 at the Letterkenny Army Depot Southeast Area
NPL site took place in 1999 when a pilot study was initiated to inject a sodium lactate solution into the plume
to serve as a carbon and energy source and promote ERD of the chlorinated VOCs. As a result of the initial
pilot study success, the Army continued with sodium lactate injections as part of the Focused Feasibility
Study (FFS), and ultimately selected ERD in the ROD as the preferred groundwater remedy at OU 10. A
total of three additional separate, month-long sodium lactate nutrient injections were performed
(August/September 2004, May/July 2005, and April/May 2007) at the site to enhance the biodegradation of
the remaining VOCs within the bedrock aquifer source area. Following these injections, groundwater
monitoring was implemented to continue to monitor the reduction of contaminant concentrations. Post
remediation data available through 2015 indicate that while some CVOCs were reduced to below MCL
cleanup levels, TCE, vinyl chloride, and benzene remain above MCL cleanup levels in a few wells (USAEC,
2017).
Cleanup Success: The Letterkenny Army Depot Southeast Area NPL Site OU 10 was treated using in situ
ERD involving multiple injections of sodium lactate to stimulate the microbial degradation of chlorinated
VOCs in the groundwater. Since the start of the remedy in 1999, VOC concentrations in on-site wells have
decreased significantly. The VOC plume has been remediated, with the exception of TCE, vinyl chloride,
and benzene in several wells. The groundwater use restrictions have been partially lifted in some areas that
are currently outside the extent of the contaminant plume. Groundwater monitoring will continue at the site
until MCLs have been met and the aquifer has been restored to drinking water quality (USAEC, 2015a;
USAEC 2015b).
Table 1. Summary of Remediation of Groundwater at Letterkenny Army Depot Southeast Area NPL
Site, OU-10
Contaminant of
Concern
Initial Maximum
Concentration (ppb) *
Maximum
Concentration
(April 2010) (ppb) **
Percent
Reduction
TCE
200
11
94.5%
Trctns-\,2-DCE
59
< 1.0
> 99%
1,1-DCE
13
0.34
97.4%
Vinyl Chloride
90
2.3
97.4%
Source: * EPA, 2006; ** EPA, 2010 ppb = parts per billion
MCL = EPA Maximum Contaminant Level ND = non-detect
References
United States Army Environmental Command: Final 2016 Annual Groundwater and Surface Water
Monitoring Report for Southeastern (SE) Area Operable Unit (OU) 10 AEDB-R Sites LEAD-090, -091, -095,
-100, -101, -128, Letterkenny Army Depot, Chambersburg, Pennsylvania. June 2017.
United States Army Environmental Command: Five-Year Review Report for Letterkenny Army Depot,
Chambersburg, Pennsylvania. March 2017.
United States Army Environmental Command: Letterkenny Army Depot Annual Groundwater Monitoring
Report. 2015a.
United States Army Environmental Command; Five-Year Review Report: Letterkenny Army Depot
Southeastern Area. 2015b.
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Appendix B
Letterkenny Army Depot Southeast Area NPL Site, OU 10
United States Environmental Protection Agency; Superfund Site Progress Profile: Letterkenny Army Depot
(SE Area). Updated June 29, 2011.
United States Army Environmental Command; Explanation of Significant Differences: Southeastern Area
Operable Unit 10. 2009
United States Army Environmental Command; Third Five-Year Review Report: Letterkenny Army Depot
Southeastern Area. 2012.
United States Army Environmental Command; Second Five-Year Review Report: Letterkenny Army Depot
Southeastern Area. 2008.
United States Army Environmental Command; Record of Decision: Letterkenny Army Depot (SE Area).
2006.
United States Army Environmental Command; Five-Year Review Report: Letterkenny Army Depot
Southeastern Area. 2001.
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Appendix B
Letterkenny Army Depot Southeast Area NPL Site, OU 10
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Appendix B
Gold Coast Oil Corporation NPL Site
Gold Coast Oil Corporation NPL Site
Site Location: Miami, Florida, Region 4
EPA ID#: FLD071307680
Regulatory Agency: U.S. EPA, Florida Department of
Environmental Protection (FDEP), Department of
Environmental Resource Management of Miami Dade
County (DERM)
Site Summary: Remedial action at the Gold Coast Oil
Corporation National Priority List (NPL) site included
the cleanup of chlorinated and non-chlorinated volatile
organic compounds (VOCs) that resulted from the
direct discharge of oil/solvent reclamation blowdown to
the soil and improper storage of waste. Key
contaminants included tetrachloroethene (PCE),
trichloroethene (TCE), transA ,2-dichloroethene (trans-
1,2-DCE), 1,1-dichloroethane (1,1-DCA), methylene
chloride, and toluene (USAGE, 2001). Remedial actions
included the excavation and disposal of visibly
contaminated soil, followed by a groundwater pump-
and-treat system outfitted with two air stripping towers.
Attempts to enhance contaminant reduction during
pump-and-treat operation, first by the addition of
hydrogen peroxide and then by pulsed pumping, did not
result in achieving the cleanup level. Therefore, the
pump-and-treat system was shut down and additional soil excavation and air sparging of groundwater
(without pump-and-treat) in two areas of suspected dense non-aqueous phase liquid (DNAPL) were
subsequently performed. This approach reduced groundwater concentrations to below federal, state, and
county cleanup levels in approximately six years
from the beginning of remedial activities (USACE,
2001). The site was deleted from the NPL in
October 1996 (EPA, 2011).
Site History: The Gold Coast Oil site is a 2 acre
property that operated as an oil and solvent
reclamation and bulk storage facility from the early
1970s until 1982. The property was owned by CSX
Transportation, but leased to Gold Coast Oil
Corporation until it lost its lease in 1982 due to
regulatory violations (EPA, 2011). Two aquifers lie
beneath the site, the Biscayne Aquifer, which is the
sole source of drinking water for Miami-Dade
County, and the deep Floridan Aquifer. The
Biscayne Aquifer (where contamination was
present) ranges from 5 to 110 feet below ground
surface (bgs), and the Floridian is at depths below
700 feet. The Biscayne and Floridan Aquifers are
not hydraulically connected (EPA, 1987). Soil and groundwater contamination in the Biscayne Aquifer, which
is an unconfined aquifer with high permeability, was first detected by the FDEP in 1980. Investigations were
conducted by FDEP, DERM, and EPA in 1981, and the facility ceased operations in 1982. The site was
placed on the NPL in 1983 and a record of decision (ROD) was issued in 1987 (EPA, 1987) while additional
remedial investigations continued. Soil and groundwater remedial actions were performed from 1989 until
Gold Coast Oil Corporation NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated and non-chlorinated VOCs
including PCE, TCE, frans-1,2-DCE, 1,1-DCA,
methylene chloride, and toluene; highest concentrations
in groundwater included 100,000 ppb PCE and 48,000
ppb TCE
¦ Media & Waste: Groundwater, Soil, DNAPL
(suspected)
¦ Plume: Contaminated groundwater plume
approximately 0.87 acre areal extent and up to 10 feet
thick
¦ Technologies:
o Soil excavation and disposal
o Pump-and-treat system with air stripping
o Localized air sparging of groundwater
¦ Major Successes:
o Removal of 883 tons of contaminated soil
o 80 million gallons of water treated and 1,961 pounds
of PCE and TCE removed
o Concentrations of irans-1,2-DCE, 1,1-DCA,
methylene chloride, and toluene below cleanup
levels within first year of pump-and-treat
o PCE arid TCE achieved federal, state, and county
cleanup levels within four years of pump-and-treat
implementation by use of localized air sparging
o Site deleted from the NPL in October 1996
Gold Coast Oil Site (EPA, 2011)
B-25
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Appendix B
Gold Coast Oil Corporation NPL Site
1995. A Site Closeout Report (Clark, 1995) documented that the remedial actions met the ROD cleanup
standards for soil and groundwater (USACE, 2001).
Extent of Contamination: Approximately 883 tons of visibly contaminated soil was removed from the site
between 1989 and 1990 before site investigations commenced. The initial area of the groundwater
contaminant plume was estimated to be 0.87 acres (based on 1990 plume maps). Based on the plume
thickness of approximately 10 feet and a porosity of 30 percent, the initial plume was estimated to be over
2.8 million gallons (Clark, 1995). As shown in Table 1, the initial concentrations of TCE and PCE detected in
the groundwater were greater than 1 percent and 60 percent of TCE and PCE solubility, respectively,
indicating the likely presence of a DNAPL (EPA, 1992).
Cleanup Approach: Preliminary site cleanup began with the excavation and off-site disposal of 683 tons of
soil contaminated with VOCs in March 1989, and an additional 200 cubic yards in March 1990 (USACE,
2001). The pump-and-treat system was constructed and began operation in July 1990, pumping at
approximately 44 gallons per minute (gpm). The extraction system included five on-site wells located in the
Biscayne Aquifer. Three extraction wells were installed at 15 feet bgs and two wells were installed 30 feet
bgs, with two of the three shallow wells (MW-11 and MW-13) located in an area suspected to contain
DNAPL. The two deep wells were placed in the same source zone area as MW-13, and the third shallow
well was located down gradient of the plume. The treatment system contained two 36-foot air stripping
towers. Effluent was injected back into the aquifer byway of three injection wells (Clark, 1995).
Several adjustments, both successful and unsuccessful, were made to the pump-and-treat system to
optimize and speed cleanup. In July 1991, wells MW-11 and MW-13 were enlarged from 2-inch to 4-inch
wells to increase extraction rates in the most contaminated area of the plume. Additionally, hydrogen
peroxide was injected into these two wells from March to July 1993, in an unsuccessful attempt to oxidize
TCE and PCE, which were still elevated (at 10 and 30 |jg/L or ppb, respectively) relative to their cleanup
levels. From August 1993 until early 1994, the groundwater extraction system was shut down periodically (or
pulsed) for periods of 30 and 60 days in an attempt to increase TCE and PCE desorption from aquifer
materials in area groundwater. This effort was also unsuccessful, and the pump-and-treat system was
permanently shut down in May 1994. From November 1994 until February 1995, the soil surrounding MW-
11 and MW-13 was excavated under suspicion that DNAPL may have been present. TCE and PCE were not
detected in excavated soil. Finally, with the pump-and-treat system shut down, the groundwater in the areas
of MW-11 and MW-13 was sparged using a portable air sparging unit in early 1995 (USACE, 2001). The
aquifer was sampled over the next three months, and showed no exceedance of contaminant cleanup
levels, which were derived from FDEP, DERM, and EPA MCLs. The cleanup levels were 3 ppb for PCE and
TCE, 70 ppb for trans-1,2-DCE, 5 ppb for 1,1-DCA and methylene chloride, and 340 ppb for toluene
(USACE, 2001).
Cleanup Success: At the Gold Coast NPL site, source removal, combined with groundwater pump-and-
treat and air sparging over a six year period, successfully reduced concentrations of chlorinated solvents to
below cleanup levels based on MCLs and other state and county standards. The pump-and-treat system
removed 1,961 pounds of TCE and PCE from 1991 to 1994, and treated a total of 80 million gallons of
groundwater. Through an iterative cleanup process, "hot spots" of residual contaminant were identified and
subsequently effectively treated.
B-26
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Appendix B
Gold Coast Oil Corporation NPL Site
Table 1. Reduction of PCE and TCE in Groundwater at the Gold Coast Oil Corp. NPL Site
Treatment Phase
PCE
Concentration
(PPb)
TCE Concentration
(PPb)
Initial Maximum Concentration
100,000
48,000
Before Pump-and-Treat (January 1990) - Average
Concentration
176
88
After Completion of Pump-and-Treat - Average
Concentration
8
9
After Completion of Localized Air Sparging - All
Concentrations
<3
<3
Sources: Clark, 1995; EPA, 1998
References
Edward E. Clark Engineers-Scientists, Inc. (Clark); Site Closeout Report, Gold Coast Oil NPL Site; January
1995.
United States Army Corps of Engineers; Superfund Five-Year Review Report. Gold Coast Oil Company,
Inc.; August 2001.
United States Environmental Protection, Region 4; Gold Coast Oil Corp, Site Summary; 2011.
United States Environmental Protection Agency; Cost and Performance Report. Pump and Treat and Air
Sparging of Contaminated Groundwater at the Gold Coast Superfund Site, Miami, Florida; September 1998
United States Environmental Protection Agency. Estimating Potential for Occurrence of DNAPL at
Superfund Sites. OSWER Publication 9355.4-07FS. January 1992.
United States Environmental Protection Agency; EPA Superfund Record of Decision. Gold Coast Oil Corp.;
1987.
B-27
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Appendix B
This Page Intentionally Left Blank
B-28
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Appendix B
Hollingsworth Solderless Terminal (OU 1)
Hollingsworth Solderless Terminal (OU 1)
Site Location: Fort Lauderdale, Florida, Region 4
EPA ID#: FLD004119581
Regulatory Agency: U.S. EPA, Florida Department of
Environmental Protection (FDEP) formerly the Florida
Department of Environmental Regulation (FDER),
Broward County Environmental Quality Control Board
(BCEQCB)
Site Summary: Remediation of the Hollingsworth
Solderless Terminal NPL site involved the application of
a number of remedial technologies, including soil
excavation and off-site disposal, pump-and-treat for
groundwater, SVE, and enhanced reductive
dechlorination (ERD). The key contaminants at the Site
are trichloroethene (TCE) and its breakdown products
cis-1,2-dichlorethene (c/'s -1,2-DCE) and vinyl chloride
in groundwater and TCE in soil. Following an initial
failed attempt at soil excavation, SVE was used to
remove soil contaminants, followed by groundwater
pump-and-treat with air stripping of the extracted
groundwater. This was followed by removal of soils in
two additional areas of contamination that were not
addressed in the original remediation, and ERD of
contaminated groundwater by the injection of potassium lactate and augmentation with Dehalococcoides
ethenogenes (DHE) bacteria. Total chlorinated volatile organic compound (VOC) concentrations in
groundwater have been reduced by up to 98 percent in just over two years after integrating in-situ ERD into
the remedial approach.
Site History: The Hollingsworth Solderless Terminal Company operated from 1968 to 1982, manufacturing
small, solderless electrical connectors. The manufacturing process included heat treatment in molten salt
baths, degreasing, and electroplating. The company disposed of wash water and process wastewater
contaminated with TCE and heavy metals into drain fields and an injection well located onsite, resulting in
contamination of soil and groundwater. The site overlies the Biscayne aquifer, which is highly permeable,
unconfined, and is composed of a fine- to-medium grained sand, sandstone, and limestone sequence. The
City of Fort Lauderdale's water supply wells are located within a quarter mile to a half mile of the
Hollingsworth Site. In the vicinity of the Site, the top of the aquifer is near ground surface and its base is
approximately 200 to 250 feet below ground surface (bgs).
In 1980, during a routine inspection, BCEQCB discovered that Hollingsworth was disposing of process
wastes into an onsite injection well. In 1981, Hollingsworth filed for bankruptcy and ceased operations the
next year. EPA conducted a Site Assessment and developed a Remedial Action Master Plan in 1982, and
the Site was listed on the NPL in 1983. In 1986, EPA finalized a feasibility study (FS) and issued a record of
decision (ROD) for the Site. A groundwater extraction and treatment system was installed in 1992 and
operated until 1994 (EPA, 2008). An explanation of significant difference (ESD) was signed in 2001 which
authorized the additional removal of contaminated soil and a septic tank from two areas that were not
treated during the original remediation. A ROD Amendment was issued in 2008 changing the groundwater
remedy from pump-and-treat to in-situ ERD (EPA, 2008). In April 2011, electron donor (Regenesis 3DMe™)
was injected in the immediate vicinity of two of the drain fields. Long term groundwater monitoring continues
at the site, a fourth five-year review was released in 2011 and a fifth five-year review in 2016.
Extent of Contamination: The VOC contaminated soil in the East Drainfield area that was treated with SVE
was estimated to be 14 feet long, 12 feet wide, and 12 feet deep, and contained total VOC concentrations as
Hollingsworth Solderless Terminal NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including TCE, c/'s-
1,2-DCE, and vinyl chloride in groundwater; TCE in soil;
highest concentrations in groundwater included 4,300
ppb TCE, 10,000 ppb c/s-1,2-DCE, and 6,000 ppb vinyl
chloride
¦ Media: Groundwater, Soil
¦ Plume: Approximate 200-foot radius area (or about 3
acres), with the highest concentrations found at the 50
to 75 foot depths
¦ Technologies:
o Soil excavation and off-site disposal
o Groundwater pump-and-treat with air stripping
o SVE
o In situ ERD with potassium lactate and
Dehalococcoides ethenogenes bacteria injections
¦ Major Successes:
o Initial groundwater remedy removed up to 55
pounds of contaminants each day
o Over 300 tons of contaminated soils removed
o Chlorinated VOC concentrations in groundwater
reduced up to 98 percent in just over two years
using ERD
o Vinyl chloride is the only remaining groundwater
contaminant detected above cleanup levels.
B-29
-------
Appendix B
Hollingsworth Solderless Terminal (OU 1)
high as 17 mg/kg (ppm) before treatment (EPA, 1996). The cleanup level for the soil was 1 ppm forTCE.
About 300 tons of contaminated soil and sludge were also excavated from the South and West Drainfields
and disposed of off-site (EPA, 2002). The extent of groundwater chlorinated VOC contamination was
estimated to be an approximate 200-foot radius area (or about 3 acres), with the highest concentrations
found at the 50-to-75-foot depths (EPA, 1986). Documents do not indicate the presence of dense non-
aqueous phase liquid (DNAPL) at the site. The established groundwater cleanup levels were 1 ppb for vinyl
chloride and 70 ppb for frans-1,2-DCE were based on the EPA proposed maximum contaminant levels
(MCLs) and 3.2 ppb for TCE was based on a 10~b life-time cancer risk factor (EPA, 1986). Subsequent
investigations determined that c/s-1,2-DCE was more prevalent than trans-1,2-DCE (EPA, 2011a).
Cleanup Approach: The cleanup approach in the ROD included excavation, ex situ aeration, and
replacement of soil in the area of excavation. The ROD also specified extraction, treatment with air stripping
technology, and re-injection of groundwater into the aquifer. Due to water levels reaching historically high
levels in the late 1980s, the soil excavation and replacement could not be completed without re-
contamination, and was replaced by in-situ SVE (Weston, 1996). The SVE system began operation in
January 1991, and by July 1991 the soil cleanup level of TCE concentrations less than 1 ppm was achieved
(Ebasco, 1993). Construction of the groundwater pump-and-treat system was completed in December 1991,
and brought online in July 1992. The system removed large volumes of VOCs at an estimated rate of over
55 pounds per day from three recovery wells during the initial weeks of operation (EPA, 2002). The system
operated until August 1994, when it was determined that the system was no longer effective at further
reducing concentrations of TCE, DCE, and VC, and the system was dismantled and removed from the site
under EPA direction (EPA, 2008).
Subsequent groundwater monitoring results showed a rebound of contaminant concentrations indicating that
residual contamination sources were present on two areas of the site. An ESD was signed by EPA in 2001,
authorizing the removal of additional contaminated soil in the South Drainfield and a septic tank in the West
Drainfield (EPA, 2008). In February 2002, soil from a 60-foot by 40-foot parcel of the South Drainfield area
was excavated to a depth of two feet below the water table (6 to 8 feet bgs). At the West Drainfield, the
septic tank was cut open, and approximately 300 tons of sludge and soil were excavated, mixed with
Portland cement, and disposed of offsite. Groundwater monitoring showed that although chlorinated VOC
concentrations had been reduced in shallow groundwater, a similar decline had not occurred in deeper
groundwater. A pilot study was performed at both the South and West Drainfields from April 2005 to
September 2007 to test the ability of in situ ERD to reduce groundwater contamination using potassium
lactate injections and bioaugmentation. At each
area, one central recovery well was installed,
screened from 6 to 36 feet bgs, and was
surrounded by a ring of eight injection wells
screened from 10 to 30 feet bgs. Groundwater
was extracted from the recovery wells, mixed with
potassium lactate solution, amended with DHE
bacteria, and injected into the aquifer. Over the
course of treatment during the pilot study, total
chlorinated VOC concentrations were reduced
from a high of 3,067 ppb to 599 ppb at the West
Drainfield, and from 60,171 ppb to 733 ppb at the
South Drainfield. Specific contaminant
concentration reductions are shown in Table 1.
Plume migration also ceased during the study.
Due to the success of the pilot study showing a
site wide decrease in contaminant concentrations,
a ROD Amendment was issued in 2008, modifying the Site remedy to in-situ ERD with potassium lactate
injection (EPA, 2008). The ROD Amendment proposed additional injections of a carbon substrate to address
the remaining unacceptable concentrations in two areas, and possible bioaugmentation with DHE bacteria.
In April 2011, an additional injection of substrate was accomplished in the two areas to address the
remaining unacceptable concentrations of groundwater contaminants (EPA, 2001b). The most recently
Treatment Plant #1, Hollingsworth Solderless
(EPA, 2011a)
B-30
-------
Appendix B
Hollingsworth Solderless Terminal (OU 1)
available groundwater monitoring data (2016) indicates that four out of the 24 wells being monitored exceed
the State of Florida standard of 1 ppb for vinyl chloride. Vinyl chloride remains the only remaining
groundwater contaminant detected above state or federal standards (EPA, 2016).
Cleanup Success: The combination of source area treatment, pump-and-treat, and in situ ERD has shown
significant progress in the remediation of the approximate 3-acre chlorinated VOC plume at the Site. The
initial groundwater pump-and-treat system removed up to 55 pounds of VOCs per day during the first weeks
of operation. Application of SVE technology to soils contaminated with TCE at concentrations up to 17 ppm
was successfully treated in six months, reducing TCE concentrations to less than the cleanup level of 1 ppm
(Ebasco, 1993). The subsequent removal of 300 tons of soil and sludge in two areas further reduced
groundwater VOC concentrations (EPA, 2002), and the implementation of in-situ ERD using injections of
potassium lactate in the two most contaminated areas of the site reduced total VOC concentrations up to 98
percent in just over two years (EPA, 2008). Recent data indicate VC is the only remaining groundwater
contaminant detected above cleanup levels.
Table 1. Reduction in Chlorinated VOC Concentrations at Hollingsworth Solderless NPL Site
TCE (ppb)
cis- 1,2-DCE
(ppb)
Vinyl
Chloride
(ppb)
Cleanup Levels
3
70
1
Maximum Initial Concentration (from 1986 ROD)a
4,300
9,700
6,000
After Pump-and-Treat (1995-1998 Data) b
0.8
10,000
2,500
Following 2002 Soil Removal (August 2002 Data)b
260
9,400
3,400
Following Pilot Study - Enhanced Reductive
Dechlorination (February and August 2007 Data)c
4.7
430
720
Current Maximum Concentrations
<3 A
<70 d
45 A
Sources: a. EPA, 1986; b. EPA, 2005; c. EPA, 2008; d. EPA, 2016
References
Ebasco; Final Remedial Action Report for the Hollingsworth Solderless Terminal Company Site; 1993.
Jackson, Galo; e-mail to Linda Fiedler with attached data from most recent Hollingsworth site sampling.
August 29, 2013.
Roy F. Weston, Inc.; Five-Year Review Report, Hollingsworth Solderless Terminal Company; 1996.
United States Environmental Protection Agency; Sampling Investigation Report, Hollingsworth Solderless
Terminal Company Superfund Site, SESD Project Identification Number: 16-0363. 2016.
United States Environmental Protection Agency; Fifth Five-Year Review Report for Hollingsworth Solderless
Terminal. September 2016.
United States Environmental Protection Agency; Fourth Five-Year Review Report for the Hollingsworth
Solderless Terminal Site; 2011a.
United States Environmental Protection Agency Hollingsworth Solderless Site Profile site; 2011b.
United States Environmental Protection Agency; Record of Decision Amendment. Hollingsworth Solderless
Terminal Company Superfund Site; 2008.
B-31
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Appendix B
Hollingsworth Solderless Terminal (OU 1)
United States Environmental Protection Agency; Third Five-Year Review Report for the Hollingsworth
Solderless Terminal Site; December 2005.
United States Environmental Protection Agency; Remedial Action Report for the Hollingsworth Solderless
Terminal Site; 2002.
United States Environmental Protection Agency; Record of Decision. Hollingsworth Solderless Terminal
Company Superfund Site; 1986.
B-32
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Appendix B
Rochester Property NPL Site
Rochester Property NPL Site
Site Location: Travelers Rest, SC, Region 4
EPA ID#: SCD980840698
Regulatory Agency: U.S. EPA
Site Summary: Remedial actions at the Rochester
Property NPL site included the cleanup of chlorinated
and non-chlorinated volatile organic compounds
(VOCs) and metals, which resulted from the dumping of
contaminated materials. Key contaminants of concern
include trichloroethene (TCE), c/'s-1,2-dichloroethene
(c/s-1,2-DCE), bis(2-ethylhexyl)phthalate, and
manganese. The initial remedial actions included an in
situ air sparging system through the saturated portion
of the aquifer. This was later followed by chemical
oxidation by adding ozone to the air sparging system
(EPA, 2005). The site was added to the NPL on
October 4, 1989 and deleted from the NPL on October
9, 2007 (EPA, 2011). EPA maximum contaminant levels (MCLs) have been achieved in groundwater site-
wide for all contaminants. Key contaminant concentrations have been reduced by at least 82 percent or
more site-wide (EPA, 2005).
Site History: The Rochester Property NPL site was used in the early 1970s as a dump site for the disposal
of various wastes including wood glue, print binders, powder materials, natural guar gums, and adhesives.
The site contains four trenches, each approximately 40 feet long, 3 feet wide, and 10 feet deep. The site is
relatively flat and is part of the Piedmont physiographic province of South Carolina. Sands, silts, clays and
underlying bedrock make up the geology at the site and depth to water ranges from 5 feet below ground
surface (bgs) to 23 feet bgs (EPA, 1993). During a 1984 inspection, chlorinated and non-chlorinated VOCs
and metals were detected during a waste analysis (EPA, 2005). Rochester Property was listed on the NPL
in 1989 and deleted from the NPL in 2007 (EPA, 2011). EPA issued a record of decision (ROD) in 1993 to
address contamination at the site and select a remedy, which was followed by an explanation of significant
difference (ESD) in 2002 to modify the remedy. To date, two five-year reviews have been released in 2000
and 2005, respectively. A second ESD was released in 2006 after the second five-year review to address a
change in remedial goals for TCE and bis(2-ethylhexyl)phthalate. Manganese was removed as a remedial
goal from this 2006 ESD due to a change in EPA's Integrated Risk Information System (IRIS) manganese
risk values.
Extent of Contamination: Dissolved phase contaminants were present in the groundwater at Rochester
Property with maximum TCE, c/'s-1,2-DCE, bis(2-ethylhexyl)phthalate, and manganese concentrations of
180 |jg/L (ppb), 3,600 ppb, 33 ppb, and 1,390 ppb, respectively (EPA, 1993). The horizontal extent of TCE
contamination was delineated to approximately 145 feet long by 100 feet wide and the extent of c/'s-1,2-DCE
contamination was delineated to approximately 135 feet long by 85 feet wide during site investigations (EPA,
2005). Initial and current groundwater contaminant concentrations are shown in Table 1.
Cleanup Approach: The first remedial actions at the Rochester Property NPL site took place in 1990 when
1,400 cubic yards of waste were excavated and disposed of off-site in a hazardous waste landfill. After the
ROD was signed in 1993, an in situ dual trench air sparging system was constructed and operated from
June 1995 until July 1999, when it was determined that the wells with the highest concentrations no longer
exceeded remedial goals. In 2000 however, groundwater sampling and analysis found increasing
contaminant concentrations in a down gradient well off-site, which was later purchased by Rochester
Property. The air sparging system was then modified in 2002 to include ozone sparging, which along with
air, improved treatment efficiency by chemically oxidizing the contaminants. The air/ozone sparging system
Rochester Property NPL Site
Remediation Highlights
¦ Contaminants: TCE, c/s-1,2-DCE, bis(2-
ethylhexyl)phthalate, and manganese; highest
concentrations in groundwater included 180 ppb TCE,
3,600 ppb c/s-1,2-DCE, 33 ppb bis(2-
ethylhexyl)phthalate, and 1,390 ppb manganese
¦ Media: Groundwater, Soil
¦ Plume: TCE groundwater plume approximately 1/3
acre in size
¦ Technologies:
o in situ air sparging
o ISCO by ozone sparging in groundwater
o Excavation of soil and offsite disposal
¦ Major Successes:
o Groundwater cleanup levels (MCLs) achieved at all
locations over nine years
o Removal of 1,400 cubic yards of contaminated soils
o Successful treatment approach using innovative in
situ technologies to accelerate cleanup
B-33
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Appendix B
Rochester Property NPL Site
was shut down in 2004 to assess potential rebound effects and continue groundwater monitoring (EPA,
2005).
Cleanup Success: The Rochester Property NPL site was treated using an innovative in situ remedial
technology which employed a chemical oxidation method by combining ozone with the original air sparging
system. Dissolved phase contaminants in groundwater were addressed and remediated successfully using
this in situ method. Overall, the key contaminants of concern were removed from the groundwater and no
longer exceed MCLs. Manganese was originally determined to exceed cleanup levels; however, the 2006
ESD removed manganese as a contaminant of concern due to a change in EPA's IRIS manganese risk
values. There have been no exceedances of MCLs since sampling in November 2004. The air sparging
system was turned off in July 2004 and the final groundwater monitoring event was conducted in November
2006, due to consistent contaminant concentrations below the MCLs. EPA has determined that the site
meets criteria for "Site-Wide Ready for Anticipated Use" and was deleted from the NPL in October, 2007.
Since cleanup was completed to levels which are sufficient for unrestricted use and exposure, there will be
no more five-year reviews for this site (EPA, 2011).
Table 1. Summary of Remediation of Groundwater at Rochester Property NPL Site
Contaminant of
Concern
Initial Maximum
Concentration (ppb)
Remedial Goal
(ppb) (MCL)
Current Maximum
Concentration (ppb)
Percent
Reduction
TCE
180
5
97%
cis- 1,2-DCE
3,600
70
97%
Bis(2-
ethylhexyl)phthalate
33
6
82%
Sources: EPA, 1993; EPA, 2005
MCL = U.S. EPA Drinking Water Maximum Contaminant Level
ppb = parts per billion
References
United States Environmental Protection Agency; Superfund Site Progress Profile. Rochester Property.
Updated March 1, 2011.
United States Environmental Protection Agency; Explanation of Significant Differences: Rochester Property.
2006
United States Environmental Protection Agency, Region 4; Superfund Five-Year Review Report: Second
Five-Year Review Report for Rochester Property Superfund Site, Travelers Rest, South Carolina. 2005.
United States Environmental Protection Agency; Explanation of Significant Differences: Rochester Property.
2002.
United States Environmental Protection Agency; Five-Year Review Report (Type 1), Rochester Property
Site, Travelers Rest, South Carolina. 2000.
United States Environmental Protection Agency; Record of Decision: Rochester Property. 1993.
B-34
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Appendix B
Tri-State Plating NPL Site
Tri-State Plating NPL Site
Site Location: Columbus, IN, Region 5
EPA ID#: IND006038764
Regulatory Agency: US EPA
Site Summary: Remedial actions at the Tri-State
Plating National Priority List (NPL) site included the
cleanup of metals from electroplating activities. The key
contaminant of concern at the site was chromium. The
initial remedial actions included disposal of drums
containing inorganic materials. Later, soil was
excavated and the onsite buildings were
decontaminated and demolished. Groundwater
contamination was addressed by a pump-and-treat
system using existing extraction wells. The site was
deleted from the NPL in July, 1997 after all cleanup
levels had been met. During cleanup, the total
chromium concentration in groundwater was reduced
below its cleanup level of 50 |jg/L (ppb) and the aquifer
was restored for unrestricted use (EPA, 1997).
Site History: The Tri-State Plating site operated from 1946 to 1981 as Hull Industries and Quality Plating
Service Company and was bought by Tri-State Plating in 1981. From 1981 to 1984, electroplating
operations were the primary activity at the 0.36-acre site. The site used chromium for plating activities.
Contamination was first detected in 1983 in both soil and groundwater after the death of six birds that drank
from a pool onsite. In 1984, after finding that Tri-State Plating was discharging contaminated wastewater to
the city's sewer system, the City of Columbus instructed the company to install a treatment system to control
the contamination. Later in 1984, when a treatment system had not been installed, the city blocked off the
sewers leading from the Tri-State Plating facility and shut off the company's water supply. Tri-State Plating
discontinued operations in 1984. The Tri-State Plating site was listed as final on the NPL in 1986. A record
of decision (ROD) was signed in 1990 and the site was deleted from the NPL in 1997 (EPA, 2011).
Extent of Contamination: Contaminants were present in the surface and subsurface soils and eventually
migrated to the underlying aquifer. Maximum initial and final monitoring groundwater contaminant
concentrations for chromium are shown in Table 1. The total extent of the groundwater plume was not
available from the information sources used for this case summary, however, elevated levels of chromium
were found in a groundwater well located 200 feet south of the site.
Cleanup Approach: The first remedial actions at Tri-State Plating took place in 1987 when 27 drums of
waste were transported and disposed of off-site. Later that year, decontamination of site buildings occurred
and the top one foot of soil and several areas of visible contamination were excavated site wide, followed by
further excavation in 1989. Also in 1989, all on-site structures were demolished and soil was re-vegetated
and graded. A groundwater extraction system was installed to remediate the chromium plume and operated
from 1992 until the groundwater remediation goals were met in 1995 (EPA, 1997; Tetra Tech, 1992). The
system used three groundwater extraction wells at depths of up to 60 feet below ground surface (bgs). It
was determined that a pump rate of 200 gallons per minute (gpm) created an effective capture zone which
prevented offsite contaminant migration. The extracted groundwater was treated by the existing City of
Columbus waste water treatment plant priorto discharge (Tetra Tech, 1992). The site groundwater was
sampled for a two-year period to assure that the groundwater cleanup goals were achieved permanently,
and the remedial activities were deemed complete in 1996 (EPA, 1997).
Cleanup Success: The Tri-State Plating site was effectively remediated using source control (drum and soil
removal) followed by the operation of a groundwater pump-and-treat system for a period of about three
Tri-State Plating NPL Site
Remediation Highlights
¦ Contaminants: Chromium; highest concentration in
groundwater 1,800 ppb.
¦ Media: Groundwater, Soil
¦ Plume: Contaminant plume extended for at least 200
feet
¦ Technologies:
o Groundwater pump-and-treat
o Excavation and off-site disposal of soil and drums
o Decontamination and demolition of site buildings
¦ Major Successes:
o Groundwater cleanup levels for chromium were
achieved in just three years of pump-and-treat
system operation
o Determined that site meets criteria for "Site-Wide
Ready for Anticipated Use," including unlimited use
and unlimited access
o Protected a municipal well field and surface water
located 800 feet from the site
o Deleted from the NPL in 1997
B-35
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Appendix B
Tri-State Plating NPL Site
years. Following remedial activities, it was determined that groundwater remedial action objectives (RAOs),
including the cleanup level of 50 ppb for chromium, were achieved and no further remediation would be
required (EPA, 1997).
Table 1. Summary of Remediation of Groundwater at Tri-State Plating NPL Site
Contaminant of
Concern
Initial Maximum
Concentration (ppb)
Cleanup Level
(ppb)
Final Maximum
Concentration (ppb)
Percent
Reduction
Chromium (Total)
1,800
50
<50
>98%
Source: EPA, 1990; EPA, 1997
ppb = parts per billion
References
TetraTech, Inc.; Remedial Action Report for Tri-State Plating Site, Columbus, Indiana. 1992.
United States Environmental Protection Agency; Superfund Site Progress Profile. Tri-State Plating. Updated
April 4, 2011.
United States Environmental Protection Agency; Notice of Intent for Deletion. Tri-State Plating Superfund
Site from the National Priorities List. 1997.
United States Environmental Protection Agency; Superfund Record of Decision: Tri-State Plating. 1990.
B-36
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Appendix B
Odessa Chromium II NPL Site
Odessa Chromium II NPL Site
Site Location: Odessa, TX, Region 6
EPA ID#: TXD980697114
Regulatory Agency: US EPA, Texas Commission of
Environmental Quality (formerly Texas Natural
Resource Conservation Commission)
Site Summary: Remedial actions at the Odessa
Chromium II NPL Site included the cleanup of total
chromium and hexavalent chromium [Cr(VI)]
contamination in groundwater, caused by radiator
repair work conducted on the site from 1960 to the
early 1970s. The initial remedy began in 1993 and
included the extraction of chromium-contaminated
groundwater, with ex situ electrochemical (South
Plume) and ion exchange (North Plume) treatment of
groundwater that exceeded the EPA maximum
contaminant level (MCL) for total chromium of 0.10
mg/L (ppm). Secondary in situ chemical reduction
(ISCR) treatment was conducted in 1999 by injecting a
concentrated ferrous sulfate [Fe(ll)S04] solution to
expedite cleanup of a small area (two wells) that
remained above remediation goals after five years of
pump-and-treat. Overall, the site achieved its cleanup
goals in less than 10 years of treatment.
Site History: Basin Radiator & Supply operated a radiator repair facility at the site from 1960 to the early
1970s. Wastewater containing corrosion inhibitors, including Cr(VI), was discharged to unlined ponds and
radiator sludge was buried at the site. Two aquifers at the site were affected (perched and Trinity) with depth
to groundwater ranging from 35 to 45 feet below ground surface (bgs) (EPA, 2005). Groundwater
contamination was first detected in 1977 when the Texas Natural Resource Conservation Commission
(TNRCC) discovered elevated levels of chromium in groundwater in response to citizen complaints of
contaminated well water (EPA, 2004). The Odessa Chromium II site was added to the state Superfund list in
1981, and listed on the NPL in 1985 (EPA, 2005). A record of decision (ROD) was signed in 1988 and two
explanation of significant differences (ESD) documents were filed in 1999 and 2003. The site was deleted
from the NPL in 2004 (EPA, 2005).
Extent of Contamination: Total chromium contamination was present in both the perched aquifer and the
Trinity-Edwards sole-source aquifer with the highest concentrations of 9.9 and 3.3 ppm, respectively (EPA,
2004). More than a 40-acre portion of the Trinity-Edwards aquifer showed contamination (EPA, 2011). The
Trinity-Edwards aquifer is 60 to 100 feet thick and lies in sandstone and conglomerate rock overlaid by 20 to
60 feet of soil and caliche (EPA, 2011). Maximum initial and final cleanup groundwater contaminant
concentrations are shown in Table 1.
Cleanup Approach: The initial remedy began in 1993 and included the extraction of chromium-
contaminated groundwater from the South Plume, with ex situ electrochemical treatment of groundwater
with chromium concentrations greater than the MCL. At the time of the initial remedy, the cleanup goal for
total chromium was 0.05 ppm, but was raised to 0.10 ppm in 1999. Treated groundwater was re-injected into
the Trinity-Edwards aquifer. By December 1997, all six wells in the Trinity-Edwards aquifer and two wells in
the perched zone exhibited total chromium concentration less than 0.10 ppm, and 141 pounds of chromium
had been removed from area groundwater (EPA, 2005). However, two wells in the perched zone remained
above cleanup levels after five years of extraction and treatment. In December 1998, both of the remaining
wells were treated with a concentrated solution of Fe(ll)S04. The wells were continuously sampled and one
Odessa Chromium II NPL Site
Remediation Highlights
¦ Contaminants: Chromium and hexavalent chromium
(CrVI); highest concentrations in groundwater included
9.9 ppm total chromium
¦ Media: Groundwater
¦ Plume Size: Chromium contamination in more than a
40-acre portion of the Trinity-Edwards aquifer
¦ Technologies:
o Groundwater pump-and-treat with ex situ ion-
exchange treatment of North Plume and
electrochemical treatment of South Plume
o ISCR using ferrous sulfate (Fe(ll)S04) treatment
¦ Major Successes:
o Pump-and-treat: six wells in Trinity Aquifer and two
wells in the perched zone achieved concentrations
<0.10 ppm
o Pump-and-treat: 141 pounds of chromium removed
from groundwater via pump-and-treat
o ISCO: two additional wells that were above 0.10
ppm achieved the cleanup goal with only two
rounds of treatment
o Successful treatment train approach using pump-
and-treat followed up by innovative ISCR to
accelerate cleanup and achieve MCLs in less than
10 years
B-37
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Appendix B
Odessa Chromium II NPL Site
of the two wells was shut down in February 1999 after three months of continuous concentrations below the
cleanup level. The second well received a second Fe(ll)S04 treatment in April 1999 as its concentration had
dropped below the cleanup level right after the first treatment but did not stay below the cleanup level during
the subsequent 90-day period. Concentrations at the second well remained below cleanup levels during the
90-day period after the second treatment.The first ESD was filed in 1999 as the PRP agreed to expand the
remedy to the North Plume and petitioned EPA to change the treatment type from electrochemical to ion
exchange, claiming lower projected remedial costs (EPA, 2005). The ESD added ISCR using Fe(ll)S04
treatment to the two remaining wells to speed the remediation process. In September, 2003 a second ESD
was filed to remove requirements for long-term monitoring since cleanup goals had been achieved. A
Closeout Report verifying the success of the Odessa Chromium II, North and South Plume remedy
remediation was signed by EPA in September 2003.
Cleanup Success: The Odessa Chromium II NPL Site was treated using a pump-and-treat system with ex
situ electrochemical and ion exchange treatment technologies. The system treated 121 million gallons of
water, removing 141 pounds of total chromium in two aquifers over a five-year period, leaving only two
perched zone wells with residual chromium concentration in excess of the cleanup goal (EPA, 2005). The
remaining two wells were treated successfully by ISCR to help reduce chromium concentrations to levels
below the cleanup goal. EPA issued an ESD on September 10, 2003, which contained sampling results from
more than eight years of quarterly monitoring. Upon evaluation of the data, it was determined that the 30-
year monitoring period requirement could be discontinued. EPA, with concurrence from the TCEQ,
determined that all appropriate responses under CERCLA had been completed and no further action was
necessary. The site was deleted from the NPL in July 2004 (EPA, 2004).
Table 1. Summary of Remediation of Groundwater at Odessa Chromium II NPL Site
Contaminant of
Concern
Initial Maximum
Concentration (ppm)
Remedial Goal (ppm)
(MCL)
Current Maximum
Concentration (ppb)
Chromium, Total
9.9
0.1
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Appendix B
Del Norte Pesticide Storage Area, OU 1
Del Norte Pesticide Storage Area, OU 1
Site Location: Crescent City, Del Norte County, CA,
Region 9
EPA ID#: CAD000626176
Regulatory Agency: U.S. EPA, State of California,
Department of Toxic Substances Control (DTSC), Del
Norte County Health and Human Services Public
Health Branch
Site Summary: Remedial actions at the Del Norte
Pesticide Storage Area included the cleanup of 1,2-
dichloropropane (1,2-DCP) and 2,4-
dichlorophenoxyacetic acid (2,4-D) from soil and
groundwater as the result of improper storage and
disposal of pesticides on the site from 1970 to 1981
(EPA, 1985). The remedy included excavation and
offsite disposal of contaminated soil and pump-and-
treat of contaminated groundwater, followed by
monitored natural attenuation (MNA) to address
residual contamination. These actions reduced 2,4-D concentrations in groundwater to below the EPA
maximum contaminant level (MCL) cleanup goal, and significantly reduced 1,2-DCP concentrations to below
the MCL cleanup goal in all but one monitoring well (EPA, 2010a).
Del Norte Pesticide NPL Site
Remediation Highlights
¦ Contaminants: Pesticides and herbicides including
1,2-DCP and 2,4-D; highest concentrations in
groundwater included 2,000 ppb 1,2-DCP
¦ Media: Groundwater, Soil
¦ Plume Size: Contaminant plume size approximately
12,000 square feet and extended approximately 170
feet off-site
¦ Technologies:
o Groundwater pump-and-treat with carbon
adsorption and air sparging
o MNA for residual 1,2-DCP
¦ Major Successes:
o 2,4-D concentration reduced below MCL in
groundwater through source removal alone
o 98 percent reduction of 1,2-DCP after only four
years of pump-and-treat
o MNA further reduced 1,2-DCP concentrations in
groundwater from 40 to 6.5 ppb
Site History: The Del Norte Pesticide Storage Area site accepted containers from local agricultural and
forestry related industries from 1970 until 1981. The site is approximately 200 feet long and 100 feet wide, or
0.5 acres. The site was used as an interim or emergency storage area for pesticide containers that had been
triple-rinsed and punctured. It was later determined that wastes and rinse water were improperly disposed of
in an unlined sump (EPA, 2010a). Area
groundwater is shallow and ranges from 3 to 10
feet below ground surface (bgs) on a seasonal
basis, and the thickness of the upper aquifer is
approximately 30 feet. The site lies on a 1.5-mile
wide marine terrace shelf, consisting of
moderately well sorted fine sands, silts, and clays
with generally moderate groundwater
permeability. Initial site investigations were
performed from 1981 to 1983, when 1,600
containers were removed from the site for proper
disposal. The site was placed on the NPL in 1983,
and a remedial investigation and feasibility study
(RI/FS) was conducted in 1985 which showed that
a 1,2-DCP and 2,4-D plume in groundwater
extended approximately 170 feet southeast of the
site. A record of decision (ROD) was signed in
1985 and an explanation of significant differences
(ESD) in 1989 determined that the chromium
contaminant of concern identified in the 1985 ROD
was naturally occurring and did not require
remediation (EPA, 2015). In 2000, a ROD amendment concluded that the remedial objective of restoring
contaminated groundwater to the MCL for 1,2-DCP would not be met because no technology existed that
was capable of reaching drinking water levels and a Technically Impracticable (Tl) waiver was issued (EPA,
2015). The site was deleted from the NPL in September 2002, and four Five-Year Reviews have been
performed, the last in June 2015. The most recent groundwater monitoring results show that all
Del Norte Pesticide Storage Site (right) and Adjacent
Airport (left) (EPA, 2010b)
B-39
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Appendix B
Del Norte Pesticide Storage Area, OU 1
contaminants of concern are below their MCLs and all remedial action objectives have been achieved (EPA,
2015).
Extent of Contamination: The soil and groundwater at the site were contaminated with 1,2-DCP and 2,4-D.
Approximately 290 cubic yards (CY) of soil required excavation and removal from the site as part of the
remedial action. The groundwater plume of 1,2-DCP, the principal contaminant, was approximately 12,000
square feet and extended 170 feet southeast of the site, with concentrations of 1,2-DCP as high as 2,000
|jg/L (ppb) before remediation (EPA, 2010a). There are no private residences or water supply wells within
2,000 feet from the plume. Concentration reductions of 1,2-DCP, by treatment phase, are shown in Table 1.
Cleanup Approach: The cleanup initially included the removal of about 290 CY of contaminated soil in
1987. The soil removal alone reduced 2,4-D concentrations in underlying groundwater to below its 100 ppb
cleanup goal at the time (EPA, 2000a). A pump-and-treat system was installed in 1990, and operated from
April 1990 to December 1994. During the period of operation, 1,2-DCP concentrations were reduced to 40
ppb, which was still above the cleanup goal of 5 ppb based on the EPA MCL adopted in 1992. With 1,2-DCP
still above its cleanup goal in groundwater, an attempt to optimize the system to further reduce 1,2-DCP
concentrations was conducted by adding air sparging and performing pulsed-pumping for extended periods
of time to determine what effect it would have on contaminant concentrations. However, the entire system
was shut down in 1997 as there were no discernible changes to the 1,2-DCP concentrations. Monitoring
data indicated that 1,2-DCP concentrations decreased at the same slow rate during air sparging and pulsed-
pumping as they had during operation of the pump-and-treat system alone. In 2000, a ROD Amendment
was issued, changing the remedy for the site to plume containment through MNA, continued groundwater
monitoring, and institutional controls. This Amendment also waived the cleanup goal for 1,2-DCP through a
Technical Impracticability Waiver (EPA, 2000b). As of October 2009, two monitoring wells had detectable
concentrations of 1,2-DCP, with only one of the wells in exceedance of the MCL (5 ppb) at a concentration
of 6.5 ppb (EPA, 2010a).
Cleanup Success: Pesticide concentrations in groundwater at the Del Norte Pesticide Storage NPL site
were significantly reduced through a combination of contaminant source removal, pump-and-treat, and
MNA. The pump-and-treat system treated 23 million gallons of groundwater in seven years of operation, and
achieved 98 percent contaminant reduction (1,2-DCP) in just its first four years (EPA, 2010a). Subsequent
MNA has further reduced 1,2-DCP concentrations to below the MCL in all monitoring wells (EPA, 2015). The
Technical Impracticability provision of the 2000 ROD Amendment will be addressed through an appropriate
Decision Document once the confirmation is received and formal documentation of unrestricted use and
unrestricted exposure status is complete (EPA, 2015).
Table 1. Reduction of 1,2-DCP Concentrations in Groundwater at Del Norte Pesticide Storage Area
NPL Site
Treatment Phase
1,2-DCP
Concentration (ppb)
Initial Concentration Before Remediation - Maximum Concentration
2,000
After Soil Removal (1989) - Maximum Concentration
600
After Initial 4 Years of Pump-and-Treat (1990-1994) - Maximum Concentration
37
After 3 Years Air Sparging (1995-1997) - Maximum Concentration
40
Natural Attenuation (by 1999) - Maximum Concentration
23
Natural Attenuation (by 2002) - Maximum Concentration
11
Natural Attenuation (by 2014) - Concentration Range in the Two Wells Where 1,2-
DCP is Still Detectable
2-4
Sources: FRTR, 2004; EPA, 2000a; EPA, 2010b; EPA, 2015
B-40
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Appendix B
Del Norte Pesticide Storage Area, OU 1
References
United States Environmental Protection Agency, Region 9; Fourth Five-Year Review for Del Norte Pesticide
Storage Area; 2015.
United States Environmental Protection Agency, Region 9; Del Norte Pesticide Storage Site Overview;
2010a.
United States Environmental Protection Agency, Region 9; Third Five-Year Review for Del Norte Pesticide
Storage Area; 2010b.
Federal Remediation Technologies Roundtable; Cost and Performance Summary Report: Air Sparging and
Pump and Treat at the Del Norte County Pesticide Storage Area Superfund Site, California; 2004.
United States Environmental Protection Agency; First Five-Year Review for Del Norte Pesticide Storage
Area; 2000a.
United States Environmental Protection Agency; EPA Superfund Record of Decision Amendment for Del
Norte Pesticide Storage; 2000b.
United States Environmental Protection Agency; Record of Decision for Remedial Action at the Del Norte
Pesticide Storage Area Superfund Site; 1985.
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Appendix B
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B-42
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Appendix B
Firestone Tire and Rubber Company NPL Site
Firestone Tire and Rubber Company NPL
Site
Site Location: Salinas, California, Region 9
EPA ID#: CAD990793887
Regulatory Agency: U.S. EPA
Site Summary: Remedial action at the Firestone Tire
and Rubber Company NPL site included cleanup of
chlorinated and non-chlorinated volatile organic
compounds (VOCs) that resulted from the spillage of
production chemicals during the manufacturing
process. Key contaminants included benzene, 1,1-
dichloroethene (1,1-DCE), 1,1-dichloroethane (1,1-
DCA), tetrachloroethene (PCE), toluene,
trichloroethene (TCE), and xylene. Remedial actions
included the removal of storage tanks, excavation of
contaminated soil, and the operation of an oil/water
separator and a groundwater pump-and-treat system
with air stripping and carbon adsorption treatment
(FRTR, 1998a and 1998b). The pump-and-treat system
operated for six years and cleanup goals were
achieved across the site. The Final Closeout Report was issued in 2004 and the site was deleted from the
NPL in April 2005 (EPA, 2009).
Site History: The Firestone Tire and Rubber Company operated a 43-acre tire manufacturing plant on this
256-acre site from 1965 to 1980. Three aquifers (shallow, intermediate, and deep) lie beneath the site, with
depths ranging from near ground surface to 90 feet below ground surface (bgs), 100 to 140 feet bgs, and
200 to 500 feet bgs, respectively. Each aquifer is separated from the neighboring aquifer by discontinuous
clay aquitards, which consist of impermeable silt and clay units. Groundwater and soil contamination was
first detected during pre-closure investigations of the facility's solid waste management units in 1983 (FRTR,
1998a). The site was placed on the NPL in July 1987 and a record of decision (ROD) was signed in
September 1989 (EPA, 2009). Remediation and monitoring activities began in 1983 and continued until
1998, and the site was deleted from the NPL in April 2005 (FRTR, 1998b).
Extent of Contamination: 1,1-DCE was the principal contaminant at the site, and was selected during the
design process as the index compound for the remedial action. The maximum concentration of 1,1-DCE
detected on-site was 120 ppb. A VOC plume was identified in groundwater that extended nearly 2.5 miles
off-site. The extent of the plume was heavily influenced by local high-volume agricultural wells which yielded
very high hydraulic conductivities, ranging from 100 to 1,200 feet/day (FRTR, 1998a). Contaminants
migrated from the shallow aquifer to the intermediate and deep aquifers by seeping through gaps in the silt
and clay aquitards separating the aquifers (FRTR, 1998b). Changes in 1,1-DCE concentrations during the
remedy are included in Table 1.
Cleanup Approach: During the pre-closure investigations conducted at the site, 11 areas of potential
contamination were identified, which led to the removal of 22 storage tanks and excavation and removal of
5,300 CY of soil contaminated with various organic and inorganic contaminants in 1983 and 1984. It was
later determined, however, that the tanks and soil removed had not been the only sources of groundwater
contamination. In 1985 a multi-component pump-and-treat system was installed, and both on-site and off-
site groundwater pumping was initiated to reduce further migration of contaminants. The extraction system
initially comprised 25 wells located on- and off-site, with 15 wells in the shallow aquifer and five wells each in
the intermediate and deep aquifers. The pump-and-treat system was not only designed to extract and treat
contaminated groundwater, but also to prevent off-site migration by placing a number of shallow wells at the
perimeter of the facility boundary (FRTR, 1998b).
Firestone Tire and Rubber NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated and non-chlorinated VOCs
including benzene, 1,1-DCE, 1,1-DCA, PCE, toluene,
TCE, and xylene; highest concentrations in
groundwater included 120 ppb 1,1-DCE
¦ Media: Groundwater, Soil
¦ Plume Size: Contaminant groundwater plume
extended 2.5 miles off-site
¦ Technologies:
o Soil removal
o Oil/water separation
o Pump-and-treat with air stripping and carbon
absorption treatment technologies
¦ Major Successes:
o Removal of 22 storage tanks and 5,300 CY of
contaminated soil
o 1.8 billion gallons of groundwater treated and 496
pounds of VOCs removed
o 1,1-DCE concentration reduced by 75 percent after
two years of pump-and-treat system operation
o All contaminants of concern below cleanup goals in
six years of pump-and-treat operation
B-43
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Appendix B
Firestone Tire and Rubber Company NPL Site
The pump-and-treat system began operation in February 1986, pumping at 550 gallons per minute (gpm)
(FRTR, 1998b). Two areas of groundwater required pre-treatment before entering the main pump-and-treat
system, due to high levels of either oil and grease or chlorinated solvents. High levels of oil and grease were
treated using an oil/water separator, followed by an initial pass through two fixed-bed adsorbers.
Groundwater with high levels of chlorinated solvents was pre-treated in an air stripper using an airflow of
750 cubic feet per minute (cfm), removing 98 percent of chlorinated solvents. All other groundwater was
mixed with water output from the fixed-bed adsorbers and the air stripping units, before passing through the
carbon filters at 550 gpm. The treated groundwater was aerated in tanks before being discharged to the
Salinas River. The pump-and-treat system operated for over six years until June 1992, when cleanup levels
for the contaminants of concerned were met. The cleanup levels were 6 ppb for 1,1 -DCE, 5 ppb for 1,1-
DCA, 3.2 ppb for TCE, 0.7 ppb for PCE and benzene, 20 ppb for toluene, and 70 ppb for xylene (EPA,
1989).
Cleanup Success: The Firestone Tire & Rubber Company NPL site remedy included source area soil
removal followed by groundwater pump-and-treat. The pump-and-treat system operated for approximately
six years, treating 1.8 billion gallons of water and removing 496 pounds of total VOCs. The decline in
concentrations of 1,1-DCE were dramatic, dropping from 120 ppb to an average of 61 ppb after the first year
of pump-and-treat system operation, halved again to an average of 30 ppb after the second year of
treatment, and dropping to 4.8 ppb by 1994. The remedial system was decommissioned in 1995 with
confirmation sampling continuing in 10 wells until 1998 (FRTR, 1998b). The Final Closeout Report was
issued in 2004 and the site was deleted from the NPL in April 2005 (EPA, 2009).
Table 1. Reduction of 1,1-DCE in Groundwater at the Firestone Tire & Rubber Company NPL Site
Treatment Phase
1,1-DCE Concentration
(PPb)
Initial Maximum Single Concentration - During Site Investigations
120
After First Year of Pump-and-Treat (1987) - Average Concentration
61
After Second Year of Pump-and-Treat (1988) - Average Concentration
-30
By 1994: After Completion of Pump-and-Treat - Average Concentration
4.8
Source: FRTR, 1998b 1,1-DCE cleanup level = 6 ppb
References
Federal Remediation Technologies Roundtable; Cost and Performance Report. Pump and Treat of
Contaminated Groundwater at the Former Firestone Facility; 1998a.
Federal Remediation Technologies Roundtable; Abstracts of Remediation Case Studies; Pump and Treat of
Contaminated Groundwater at the Former Firestone Facility Superfund Site, Salinas, California; Vol. 3, pps.
102, 103; 1998b.
United States Environmental Protection, Region 9; Firestone Tire and Rubber Co. (Salinas Plant), Site
Overview, 2009.
United States Environmental Protection Agency; Record of Decision. Firestone Tire & Rubber Co. (Salinas
Plant), September 13, 1989.
United States Environmental Protection Agency Web site; Undated.
B-44
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Appendix B
Pemaco NPL Site
Pemaco NPL Site
Site Location: Maywood, CA, Region 9
EPA ID#: CAD980737092
Regulatory Agency: U.S. EPA
Site Summary: Remedial actions at the Pemaco NPL
site included the cleanup of chlorinated volatile organic
compounds (VOCs), non-chlorinated VOCs, semi-
volatile organic compounds (SVOCs), PAHs, metals,
and dense non-aqueous phase liquids (DNAPLs) from
chemical blending and distribution activities. Key
contaminants of concern in the exposition groundwater
zones include tetrachloroethene (PCE), trichloroethene
(TCE), c/s-1,2-dichloroethene (c/s-1,2-DCE), and vinyl
chloride. The initial remedial actions included
contaminated soil excavation and removal of
underground and above ground storage tanks and
drums, and building demolition. These actions were
later followed by soil-vapor extraction (SVE),
groundwater pump-and-treat using granulated activated
carbon (GAC) treatment, and electrical resistance
heating (ERH) using high-vacuum dual-phase
extraction (HVDPE) and flameless thermal oxidation
(FTO). The site was added to the NPL on January 19,
1999 and has not yet been deleted; however significant
progress towards achieving remedial action objectives has been made. Groundwater contaminant
concentrations have been reduced from as high as 22,000 pg/L (ppb) TCE to below EPA maximum
contaminant levels (MCLs) in many locations. In the most successful area, eleven of 18 wells have achieved
VOC concentrations below MCLs. Additionally, contaminant concentrations in soil met cleanup levlels in
nearly all post-remediation samples (EPA, 2010). However, increasing levels of contamination since 2011
indicate that the full lateral and vertical extent of TCE contamination has not been fully delineated (EPA
2015).
Site History: Pemaco operated from the 1940s to 1990s as a chemical blending and distribution facility until
the owner abandoned the site in 1991. The site used chlorinated and aromatic solvents, oils, and other
flammable liquids, which were stored on-site. The main
warehouse, which is the principal source of contamination
on-site, was destroyed by a fire in 1993 (EPA, 2011). The
4.1-acre site is relatively flat and consists of six discrete
groundwater areas. A perched aquifer zone ranges from 30-
35 feet below ground surface (bgs) and the remaining five
underlying zones range from 3 feet to 15 feet thick at depths
ranging from 75-175 feet bgs. There is a 1-10-foot
impermeable clay layer that lies directly beneath the
perched zone, separating the upper and lower aquifers. The
five underlying zones are made up of silty sands separated
by less permeable clay-rich strata and are stratigraphic
equivalents to the regional Exposition Aquifer (EPA, 2010).
Pemaco was listed on the NPL in 1999 and has not yet
been deleted (EPA, 2011). A site Feasibility Study (TN&A,
2004) was issued in 2004 and a record of decision (ROD)
(EPA, 2005) was signed in 2005. The First Five-Year Review Report was completed in 2010 and a second
Five-Year Review Report was completed in 2015.
Pemaco NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including PCE, TCE,
c/s-1,2-DCE, and vinyl chloride; non-chlorinated VOCs;
SVOCs including PAHs, and metals; highest
concentrations in the exposition groundwater zone
included 1,100 ppb PCE, 22,000 ppb TCE, 14,000 ppb
DCE, and 780 ppb vinyl chloride
¦ Media: Groundwater, Soil, DNA.PL (suspected)
¦ Plume Size: VOC groundwater plume approximately
1,300 feet by 750 feet in deep aquifer, extended 200
feet offsite in perched aquifer
¦ Technologies:
o High-vacuum dual phase extraction
o ERH
o Groundwater pump-and-treat (GAC/UV Ox)
o Excavation and off-site disposal of soil
¦ Major Successes:
o Groundwater and soil cleanup levels achieved at
most locations; reduced groundwater contaminant
concentrations to below MCLs at most locations
o Removal and treatment of 21,500 pounds of VOCs
in vadose zone soils
o Remediation of DNAPL
o Successful treatment approach using innovative, in
situ technologies to accelerate cleanup
o Redevelopment of the site into a park
Groundwater Treatment Facility at Pemaco
Superfund Site (EPA, 2010)
B-45
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Appendix B
Pemaco NPL Site
Extent of Contamination: Dissolved phase contaminants and DNAPL were present in the perched aquifer,
with VOC concentrations exceeding 10,000 ppb. The lateral extent of contamination within this aquifer
extended off-site over 200 feet from site boundaries. Contaminants migrated to the upper zones of the
deeper "Exposition Aquifers" where DNAPL was suspected due to the presence of TCE at greater than 1
percent of its solubility (EPA, 1992). The deeper plume extended laterally over an area of 1,300 feet by 750
feet, with a thickness of 1.5 to 10 feet, with VOC concentrations at a maximum of 22,000 ppb in the source
area (EPA, 2010). Initial and subsequent groundwater contaminant concentrations as of 2011 are shown in
Table 1.
Table 1. Summary of Remediation of Groundwater at Pemaco NPL Site
Contaminant of
Concern
Initial Maximum
Concentration (ppb)
Remedial Goal
(ppb) (MCL)
2011 Maximum
Concentration (ppb)*
Percent
Reduction
PCE
1,100
5
120
89%
TCE
22,000
5
650
97%
cis- 1,2-DCE
14,000
6
450
97%
Vinyl Chloride
780
0.5
16
98%
Sources: EPA, 2005; EPA, 2010
MCL = U.S. EPA Drinking Water Maximum Contaminant Level
ppb = parts per billion
* Concentrations have increased since 2011 because the full extent of contamination has not been determined.
Cleanup Approach: The first remedial actions at the Pemaco NPL site took place from 1991 to 1999, when
emergency removal activities were initiated. These activities included soil excavation and removal of
underground and above ground storage tanks and drums. In 1997, an SVE system was installed as an
interim treatment method. It remained operational until 1998, when it was shut down due to community
concerns about dioxin emissions from the SVE system which could have been produced as a byproduct of
the thermal oxidation treatment of extracted vapors. By the time the SVE system was removed, it had
treated over 21,500 pounds of hydrocarbons from vadose zone soils. After the ROD was signed in 2005,
construction began on additional selected remedies. These remedies, which began in 2007, included a
HVDPE pump-and-treat system which used GAC for groundwater treatment and FTO/GAC for treatment of
vapors. In addition, ERH was used to treat the deeper vadose soils and groundwater at depths from 32 feet
to 100 feet bgs, which was to be followed by groundwater pump-and-treat and monitored natural attenuation
(MNA) (EPA, 2005; EPA, 2011). A bioremediation pilot study was also initiated in 2006, and has shown
favorable conditions for reductive dechlorination of TCE. EPA is evaluating potential optimization
opportunities, including additional bioremediation treatment, reduced pumping rates, and or pulsed pumping.
In 2007, the site also performed an in situ bioremediation pilot study using enhanced reductive
dechlorination (ERD), both alone and in conjunction with thermal treatment using ERH.
Cleanup Success: The contaminated vadose and saturated zones at the Pemaco NPL site were treated
using several innovative remedial technologies. Dissolved phase contaminants, DNAPL, and soil vapor were
addressed using these technologies. The site was separated into various areas (northern, which included
pump-and-treat and SVE, and southern, which included ERH and source zones). While all areas have
shown significant progress, the southern ERH target zone has shown the most success. In this area, the
HVDPE system removed 70 percent of the contaminant mass, which was followed by removal of the
remaining 30 percent by ERH. Eleven of 18 wells in the southern area have shown TCE concentrations
below the MCLs, however, there are still wells that have not achieved MCLs (although only three of the wells
in this area have concentrations above 25 ppb). However, increasing levels of contamination since 2011
indicate that the full lateral and vertical extent of TCE contamination has not been fully delineated (EPA
2015). Nearly all soil samples taken post-ERH have concentrations below 10 ppb TCE, achieving the
cleanup level of 60 ppb for soil. The Pemaco site has not yet been deleted and groundwater pump-and-treat
and MNA will continue until groundwater MCLs are met site-wide. However, the Maywood Riverfront Park,
which includes the redeveloped Pemaco site, officially opened in May 2008 and offers soccer fields,
playground equipment, handball courts, and basketball courts for area residents.
B-46
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Appendix B
Pemaco NPL Site
References
T N & Associates, Inc. (TN&A); Final Feasibility Study Report. Pemaco Superfund Site. 2004.
United States Environmental Protection Agency, Region 9; Second Five-Year Review Report for Pemaco
Superfund Site: Los Angeles County, California. 2015.
United States Environmental Protection Agency; Superfund Site Progress Profile. Pemaco. Updated March
14, 2011.
United States Environmental Protection Agency, Region 9; First Five-Year Review Report for Pemaco
Superfund Site: Maywood, California. September 2010.
United States Environmental Protection Agency, Return to use Initiative. Pemaco Maywood, CA. 2009.
United States Environmental Protection Agency; Record of Decision for Pemaco Superfund Site: Maywood,
California. 2005.
United States Environmental Protection Agency. Estimating Potential for Occurrence of DNAPL at
Superfund Sites. OSWER Publication 9355.4-07FS. January 1992.
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Appendix B
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Appendix B
Southern California Edison Co., Visalia Pole Yard NPL Site
Southern California Edison Co., Visalia Pole
Yard NPL Site
Site Location: Visalia, CA, Region 9
EPA ID#: CAD980816466
Regulatory Agency: U.S. EPA, State of California
Department of Toxic Substances Control
Site Summary: Remedial actions at the Southern
California Edison (SCE) Visalia Pole Yard NPL site
included the cleanup of chlorinated and non-chlorinated
SVOCs from wood treatment activities. Key contaminants
of concern include benzo(a)pyrene, pentachlorophenol
(PCP), and tetrachlorodibenzo-p-dioxin (TCDD), an
impurity in the PCP used at the site. The initial remedial
actions included installation of a vertical engineered
barrier (VEB) (slurry wall) to keep contaminants from
migrating offsite, contaminated soil removal and
groundwater pump-and-treat. To enhance the removal of
contaminants, an in situ thermal treatment system using
steam injection in a dynamic underground stripping (DUS)
process was implemented, followed by in situ
bioremediation using air sparging and bioventing. The site
was deleted from the NPL in September 2009 after all
remedial action objectives (RAOs) had been met. Overall, approximately 1.33 million pounds of
contaminants were removed or treated during remedial actions, reducing groundwater contaminant
concentrations, which ranged from 5 ppb to 610 ppb, to below EPA MCLs. Contaminant concentrations in
soil also met cleanup levels as determined in the ROD (Eaker, 2010).
Visalia Pole Yard NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated and non-chlorinated SVOCs
including benzo(a)pyrene, PCP, and TCDD; highest
concentrations in groundwater included 5 ppb
benzo(a)pyrene, 610 ppb PCP, and 11 ppb TCDD
¦ Media & Waste: Groundwater, Soil, DNAPL
¦ Plume Size: SVOC groundwater plume covers 2.1 acres
and extends from the water table to a depth of
approximately 145 feet
¦ Technologies:
o In situ thermal treatment (DUS)
o In situ bioremediation (air sparging and bioventing)
o Groundwater pump-and-treat
o VEB (slurry wall)
o Excavation and off-site disposal of soil
¦ Major Successes:
o All groundwater and soil cleanup levels achieved;
reduced groundwater contaminant concentrations to
below MCLs
o Removal or treatment of 1.33 million pounds of
contaminants
o Remediation of DNAPL
o Successful treatment train approach using innovative,
in situ technoloaies to accelerate cleanup
Extent of Contamination: Dissolved phase
contaminants were present in the shallow aquifer
and eventually migrated to the intermediate and
deeper aquifers. Contaminant migration also occi
settled at the bottom of the shallow (50 feet bgs) ¦<
Contaminants in a dissolved air flotation tank at Visalia
Pole Yard (Walter, 1998)
ed laterally along the aquitards and pools of DNAPL
d intermediate (100 feet bgs) aquifers. Contaminants
Site History: The SCE Visalia Pole Yard operated from 1925 to 1980 as a utility pole treatment facility. The
site used creosote compounds and PCP dissolved in diesel oil from 1968 to 1980. Leaks from pipes and
underground storage tanks (LJSTs) contaminated soil and groundwater at the site. Three aquifers (shallow,
intermediate, and deeper) consisting of unconsolidated sediment lie beneath the site, ranging in depth from
30 to 180 feet below ground surface (bgs). Aquitards consisting of a relatively impermeable silt layer
separate these aquifers (EPA, 1994). Groundwater contamination was first detected in 1966 in an onsite
well. The Southern California Edison Visalia Pole
Yard was added to the state Superfund list in
1985, then was listed on the NPL in 1989 and
deleted in 2009 (EPA, 2011) A record of
decision (ROD) was signed in 1994 and three
five-year reviews have occurred to date (2005,
2010, and 2015). The Remedial Action
Completion Report (SCE, 2008) documented that
the post-remediation groundwater monitoring and
soil removal actions performed met the ROD
cleanup standards for soil and groundwater. A
Remedial Action Report and a final close out
report were signed in 2009 (EPA, 2009).
B-49
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Appendix B
Southern California Edison Co., Visalia Pole Yard NPL Site
migrated into the deep aquifer to a maximum depth of 145 feet bgs(EPA, 1994). Maximum initial and
subsequent groundwater contaminant concentrations as of 2007 are shown in Table 1.
Cleanup Approach: The first response actions at Visalia took place in 1977, when a 60-foot deep VEB
(slurry wall) was built around the contaminated area in an attempt to slow the lateral migration of
contaminants in the shallow aquifer. In 1981, 2,300 cubic yards of contaminated soil were disposed of offsite
as an initial remediation effort. A groundwater extraction and treatment system was installed and operated
from 1985 through 2004 to remediate the groundwater plume. The system pumped, treated, and discharged
an average of 0.36 to 0.5 million gallons per day of contaminated groundwater. In 1997, a DUS system was
installed using technology developed by the Lawrence Livermore National Laboratory with the University of
California, Berkeley (EPA, 2005). The DUS system was implemented to increase the rate of recovery of
contaminants, resulting in a faster and less expensive cleanup of the site. The DUS system ran for 36
months and injected 660 million pounds of steam into the saturated zone through 14 injection wells. The
liquid and vapors were extracted through four extraction wells, separated, cooled, and then treated. Daily
contaminant mass recovery rates reduced from 13,000 pounds per day initially to about 4 pounds per day by
June 2000. Steam injection was halted due to the diminishing recovery rate. After the DUS system was shut
down in 2000, in situ bioremediation (including vadose zone bioventing and saturated zone biosparging) and
pump-and-treat continued until 2004. The bioremediation phase took advantage of the elevated subsurface
temperatures to oxidize contaminants that were not removed or destroyed by the DUS process, which
enhanced the biological degradation process. Overall, approximately 1.33 million pounds of contaminants
were removed during the remedy, including 239,000 pounds by vapor phase extraction, 678,000 pounds by
free phase extraction, 199,500 pounds by aqueous phase extraction, and 212,200 pounds by in situ hydrous
pyrolysis oxidation (Eaker, 2010). A post-remediation soil investigation in November 2004 indicated that
TCDD was detected slightly above the cleanup standards at four locations. As a result, approximately 20
cubic feet within the TCDD "hot spot" area (soil between zero and 10 feet below grade) was removed in July
2006 (EPA, 2010).
Cleanup Success: The SCE Visalia Pole Yard site was treated using an innovative steam remediation
system, coupled with enhanced in situ bioremediation and pump-and-treat. While SCE estimated that the
pump-and-treat system combined with in situ bioremediation would take 120 years to clean up the site
(Walter, 1998), cleanup levels were met in less than 25 years from start of remediation and 15 years from
ROD signature. The in situ steam remediation removed over 99 percent of the contamination in just three
years. Quarterly groundwater monitoring was conducted from 1985 through June 2007, which verified that
all groundwater cleanup levels were met.
A covenant between SCE and the California Department of Toxics Substance Control prohibits use of the
site for residences, hospitals, schools, and day care centers as well as prohibiting the installation of water
wells for any purpose (EPA, 2009). EPA determined that the site meets criteria for "Site-Wide Ready for
Anticipated Use" (EPA, 2011). The Visalia Pole Yard was deleted from the NPL in 2009.
B-50
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Appendix B
Southern California Edison Co., Visalia Pole Yard NPL Site
Table 1. Summary of Remediation of Groundwater at Southern California Edison Visalia Pole Yard
NPL Site
Contaminant of
Concern
Initial Maximum
Concentration (ppb)
Remedial Goal
(ppb) (MCL)
Maximum
Concentration (ppb)
(2007)
Percent
Reduction
Benzo(a)pyrene
5
0.2
96%
PCP
610
1
99%
TCDD (Dioxin)
11
0.00003
99%
Source: EPA, 2005
MCL = U.S. EPA Drinking Water Maximum Contaminant Level
ppb = parts per billion
References
Eaker, Craig. Visalia Pole Yard: Delisting a Former Wood Treater Site Following Steam Enhanced
Extraction. Southern California Edison. Battelle Conference. 2010.
Southern California Edison Company; Visalia Pole Yard Remedial Action Completion Report. 2008.
United States Environmental Protection Agency; Superfund Site Progress Profile. Southern California
Edison Co. (Visalia Pole Yard). Updated February 16, 2011.
United States Environmental Protection Agency; Second 5-Year Review. Southern California Edison Co.
(Visalia Pole Yard). 2010.
United States Environmental Protection Agency; Final Close Out Report. Southern California Edison Co.
(Visalia Pole Yard). 2009.
United States Environmental Protection Agency; Remedial Action Report for Soil and Groundwater,
Southern California Edison Co. (Visalia Pole Yard). 2009.
United States Environmental Protection Agency; First 5-Year Review. Southern California Edison Co.
(Visalia Pole Yard). 2005.
United States Environmental Protection Agency Superfund; Record of Decision: Southern California Edison
Co. (Visalia Pole Yard). 1994.
Walter, Katie. 1998. They All Like It Hot: Faster Cleanup of Contaminated Soil and Groundwater.
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Appendix B
Western Pacific Railroad NPL Site
Western Pacific Railroad NPL Site
Site Location: Oroville, CA, Region 9
EPA ID#: CAD980894679
Regulatory Agency: US EPA, California Regional
Water Quality Control Board (CRWQCB)
Site Summary: The remediation of the Western Pacific
Railroad NPL site involved an initial removal action
addressing a waste pond and a leaking underground
storage tank (UST); the installation and operation of
groundwater pump-and-treat and soil vapor extraction
(SVE) systems, and a subsequent soil removal action.
Key contaminants were chlorinated volatile organic
compounds (VOCs) including 1,1-dichloroethane (1.1-
DCA), 1,1-dichloroethene (1,1-DCE), and
trichloroethene (TCE) in groundwater and subsurface
soil, and polycyclic aromatic hydrocarbons (PAHs) in
surface soil. Many of the response actions were
expedited and occurred prior to the signing of the
record of decision (ROD). Ultimately, the remedial
action objectives (RAOs) and groundwater cleanup
levels [(EPA and California maximum contaminant
levels (MCLs)] were met and the site was deleted from
the NPL only four years after the ROD was issued and
11 years after removal actions began.
Site History: The 90-acre Western Pacific Railroad
facility operated as a fueling and maintenance rail yard
from the 1880s until 1970. Western Pacific Railroad
and its subsequent owner, Union Pacific Railroad
(UPRR), leased the property to Solano Railcar
Company, which conducted sandblasting, painting,
welding, and railcar repairs until 1991. In the course of
the fueling, machining, and repairing of locomotives
and railcars, spills contaminated soils and
groundwater. A leaking UST in the fueling area was
the source of VOC contamination in the groundwater.
The subsurface of the site is composed of interbedded
clays, sands, and gravels, which vary in thickness and
composition, both horizontally and vertically across the
site. The depth to the shallow aquifer is approximately
60 feet below ground surface (bgs) with a genera!
groundwater flow direction to the west-southwest
toward the Feather River. A shallow clay aquitard is
located approximately 110 feet bgs at the site. In 1989,
the California Regional Water Quality Control Board (CRWQCB) issued an order to UPRR to investigate
groundwater and an on-site waste pond. The site was listed on the NPL in 1990, and UPPR signed an
Administrative Consent Order in 1993 to contain the VOC plume. The Remedial Investigation (Rl) and
Feasibility Study (FS) was completed and a ROD was signed in 1997 (EPA, 1997). Response actions were
performed through the 1990s, and the site was deleted from the NPL in 2001 (EPA, 2003).
Extent of Contamination: During the Rl, surface soils were found to be contaminated primarily with PAHs
and heavy metals, including arsenic and lead. Maximum concentrations detected were 28 mg/kg (ppm)
Western Pacific Railroad NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including 1,1-DCA,
1,1-DCE, and TCE in groundwater; PAHs, arsenic, and
lead in surface soil; highest concentrations in
groundwater 320 ppb 1,1-DCE and 66 ppb 1,1-DCA
¦ Media: Groundwater, Soil
¦ Plume: VOC plume extended approximately 700 feet
long at a depth of 60 feet bgs
¦ Technologies:
o Soil removal
o Groundwater pump-and-treat with air stripping and
GAC
o SVE
¦ Major Successes:
o 2,500 tons of PAH contaminated soil removed
o 127 million gallons of groundwater treated
o 66 pounds VOCs removed from groundwater and
soil
o Groundwater cleaned up below EPA and California
MCL
o Site deleted from the NPL 11 years after removal
actions began and only four years after ROD was
issued
RosgSlroot!
[Mill; Street!
Summers Street
"strootl
C inton
[AmoldAv
Aerial Photo (CH2M Hill, 2008)
B-53
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Appendix B
Western Pacific Railroad NPL Site
PAHs, 73 ppm arsenic, and 810 ppm lead (EPA, 1997). Removal of approximately 2,500 cubic yards (CY) of
contaminated soil was required to reach the PAH soil cleanup level of 0.41 ppm (expressed as
benzo(a)pyrene [B(a)P] equivalents). In groundwater 1,1-DCA, 1,1-DCE, and TCE were detected at
concentrations as high as 66 |jg/L (ppb), 320 ppb, and 13 ppb, respectively (Dames & Moore, 1989). The
groundwater chlorinated VOC plume spread approximately 700 feet down gradient from the site UST
towards a California Water Service (CWS) public drinking water well (CWS-1). PAHs were not detected in
groundwater.
Cleanup Approach: Cleanup at the Western Pacific Railroad NPL site started in 1989 when the waste pond
was excavated and backfilled with clean fill, groundwater monitoring wells were installed in the fueling area,
and the leaking UST in the fueling area was removed (URS, 2001). In 1994, a time-critical removal action
was conducted that involved the installation of a groundwater pump-and-treat system in the upper aquifer to
prevent migration of contaminants to a nearby public water supply well (CWS-1). The pump-and-treat
system consisted of a single extraction well, a bag filter, an air stripper, two granulated activated carbon
(GAC) units, and one injection well (EPA, 2001). The pump-and-treat system was modified at two different
times during the cleanup. In 1996, EPA allowed removal of the GAC units as use of the air stripper was
successful in removing contaminants. In 1997 a new extraction well and an SVE unit was added to expedite
and optimize contaminant removal (EPA, 2003).
By 1997, only three years after beginning pump-and-treat, and before signing of the ROD, groundwater
concentrations had reached their cleanup levels, which were based on EPA and California MCLs (whichever
was lower). The TCE cleanup level was based on the EPA MCL of 5 ppb while the 1,1-DCA and 1,1-DCE
cleanup levels were based on the California MCLs of 5 ppb and 6 ppb, respectively. As part of the ROD,
treatment and monitoring continued over the next two years to ensure that groundwater concentrations
remained below these cleanup levels. Additionally, in accordance with the ROD, a soil removal action was
conducted in 1998 over a six-day period that removed the top 1 foot of soil over a one-acre area
(approximately 2,500 CY) with the highest levels of PAH contamination. The groundwater pump-and-treat
and SVE systems were shut down in November 1999, and a final round of groundwater sampling conducted
in July 2000 confirmed that all contaminants remained below the cleanup levels. More than 127 million
gallons of groundwater were treated during the remedy, with over 66 pounds of VOCs removed from
groundwater and soil via the groundwater pump-and-treat and the SVE systems (URS, 2001). The final
closeout report for the site was signed by EPA in June 2001 (EPA, 2001).
Cleanup Success: The successful remediation of the Western Pacific Railroad NPL site involved a
combination of source removal of the waste pond, contaminated soil, and a leaking UST, followed by the
operation and optimization of a groundwater pump-and-treat and SVE system to contain and clean up a
700-foot long chlorinated VOC plume. Ultimately, the groundwater met its federal and state cleanup levels,
and the site was deleted from the NPL 11 years after removal actions began and only four years after the
ROD was signed (URS, 2001).
Table 1. Western Pacific Railroad NPL Site Groundwater Contaminant Levels
Concentrations at MW-89-2
1,1-DCA (ppb)
1,1-DCE (ppb)
TCE (ppb)
1989 (Prior to NPL listing)
66
320
13
2002 (Five Year Review)
1.4
1.7
Not Detected
Cleanup Levels
5 (CA MCL)
6 (CA MCL)
5 (EPA MCL)
Sources: Dames & Moore, 1989 (1989 data); EPA, 2003 (2002 data)
B-54
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Appendix B
Western Pacific Railroad NPL Site
References
Agency for Toxic Substance and Disease Registry; Public Health Assessment Western Pacific Railroad,
Oroville, Butte County, California; 1992
Dames and Moore; Fueling Area Progress Report; 1989.
United States Environmental Protection Agency; First Five-Year Review Report for Western Pacific Railroad
Superfund Site, Oroville, California; 2003.
United States Environmental Protection Agency; Final Close Out Report. Western Pacific Railroad
Superfund Site, Oroville, Butte County, California; 2001.
United States Environmental Protection Agency, Region 9; Record of Decision. Western Pacific Railroad,
Oroville, California; 1997.
URS Corporation; Final Remedial Action Report. Western Pacific Railroad Superfund Site, Oroville,
California; 2001.
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Appendix B
Fort Lewis Logistics Center East Gate Disposal Yard (EGDY) OU1
Fort Lewis Logistics Center East Gate
Disposal Yard (EGDY) OU1
Site Location: Pierce County, Washington, Region 10
EPA ID#: WA7210090067
Regulatory Agency: U.S. EPA, Washington State
Department of Ecology
Site Summary: The 87,000-acre former Fort Lewis
Army facility (now called Joint Base Lewis-McChord)
contains 16 Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) sites. The
Logistics Center is the largest and most affected area
at the facility, and consists of three major contaminated
waste units, including the East Gate Disposal Yard
(EGDY), the Solvent Refined Coal Pilot Project
(SRCPP) area, and Landfill 4. The focus of this case
summary is the EGDY (OU 1), which is a former
industrial landfill used for disposing of equipment
cleaning wastes and degreasing wastes.
Trichloroethene (TCE) and petroleum hydrocarbons are
the primary contaminants at the site, often occurring as
light non-aqueous phase liquids (LNAPL) and dense
non-aqueous phase liquids (DNAPLs), respectively. The remedial action at the EGDY involved connecting
private drinking water wells to clean water sources, excavation and removal of over 1,000 buried waste
drums, in situ thermal treatment of DNAPL using electrical resistance heating (ERH), and construction and
operation of pump-and-treat systems to remediate volatile organic compounds (VOCs) in groundwater (EPA,
2011). While not yet deleted from the NPL, the remedy has shown significant progress towards restoring
groundwater to EPA maximum contaminant levels (MCLs) (U.S. Army, 2007). TCE concentrations have
been decreasing, with TCE exceeding the MCL cleanup level in one well and at the MCL in one well. All
other monitoring wells are below the MCL (U.S. Army, July, 2016).
Site History: The Logistics Center is a 650-acre area located within the Fort Lewis Army facility. The facility
was built in the early 1940s, and is an industrial complex comprised of warehouses, motor pools,
maintenance facilities, and an equipment disposal yard. A 1986 groundwater investigation by the
Department of Defense (DoD) discovered TCE contamination, originating from the Logistics Center. The
source of TCE contamination was from the disposal of cleaning and degreasing wastes at the 23-acre
EGDY (also known as Landfill 2). The TCE contaminated the unconfined Vashon Aquifer and eventually
migrated to the deeper Sea Level Aquifer (SLA). While the hydrostratigraphy at the site is extremely diverse
and complex, the unconfined Vashon Aquifer generally consists of glacial sand and gravel deposits with till
layers overlying a finer-grained nonglacial deposit (Kitsap Formation). The Kitsap Formation separates the
unconfined Vashon Aquifer from the SLA. The water table is between 7 and 35 feet below ground surface
(bgs) at the site (EPA, 1990).
The Logistics Center was listed on the NPL in 1989 and a Federal Facility Agreement (FFA) was signed in
1990 between EPA, the Army, and the State of Washington Department of Ecology. The Remedial
Investigation (Rl) and Feasibility Study (FS) were completed in 1988 and 1990, respectively, and a record of
decision (ROD) was signed in 1990. Remedial activities began in the early 1990s and continue today. Due
to additional groundwater contamination identified in the lower SLA, a 2007 explanation of significant
differences (ESD) was developed, and in October 2009 the Army completed installation of an additional
pump-and-treat system for the SLA. Pump-and-treat and long term monitoring continue as of late 2016.
(EPA, 2016).
Fort Lewis Logistics Center NPL Site
Remediation Highlights
¦ Contaminants: Chlorinated VOCs including TCE and
petroleum hydrocarbons; highest concentrations in
groundwater included 250,000 ppb TCE
¦ Media & Waste: Groundwater, Soil, DNAPL
¦ Plume: TCE groundwater plume extended 2 to 2.5
miles long and 3,000 to 4,000 feet wide, with 60 to 100-
foot contaminant thickness
¦ Technologies:
o ERH
o Pump-and-treat system with air stripping treatment
o Drum waste removal
¦ Major Successes:
o Over 125,000 pounds of chlorinated VOCs and
petroleum contaminants removed by ERH in
approximately three years
o 12,787 pounds of VOCs (TCE and DCE) extracted
by pump-and-treat beginning in 1995
o Maximum groundwater TCE concentrations reduced
from over 100,000 ppb to less than 300 ppb in the
source area since 2005
o Received 2005 Secretary of Defense Environmental
Award for Environmental Restoration
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Appendix B
Fort Lewis Logistics Center East Gate Disposal Yard (EGDY) OU1
Extent of Contamination: The Logistics Center TCE groundwater plume within the Vashon Aquifer extends
from southeast to northwest for about 2 miles, is between 3,000 to 4,000 feet wide, and has a contaminated
thickness of 60 to 100 feet (EPA, 1990; U.S. Army, 2007). Partway down the plume, the Vashon Aquifer
plume divides into an Upper Vashon Aquifer plume and a Lower Vashon Aquifer plume. About halfway down
the Vashon Aquifer plume, TCE also migrated into the SLA via a hydrogeologic preferential pathway, which
created a plume that extends for approximately 2.5 miles. The 23-acre EGDY source area historically
contained TCE in groundwater at maximum concentrations exceeding 100,000 ppb (and as high as 250,000
ppb) prior to treatment. Three separate NAPL source areas covered approximately 2.2 acres at depths
ranging from 28 to 47 feet bgs (USAGE, 2002). The maximum initial and available groundwater contaminant
concentrations as of 2015 are shown in Table 1.
Cleanup Approach: Remedial action at the Logistics Center NPL site started in 1992 with the construction
of one pump-and-treat system at the EGDY and one down gradient pump-and-treat system (Interstate 5
system) near the leading edge of the plume to contain the Vashon Aquifer plume. As of 2011, the EGDY
system has eight extraction wells and the Interstate 5 system has 15 extraction wells. The Interstate 5
system extracts water only from the Upper Vashon Aquifer, so the extent to which it helps contain the Lower
Vashon Aquifer plume is unknown. The two pump-and-treat systems began operating in 1995 with a
combined design flow rate of 2,400 gallons per
minute (gpm). The systems use air stripping towers
to remove VOCs, and treated groundwater is
reinjected into the aquifer through infiltration
galleries and injection wells. Between 2000 and
2001, the Army excavated and removed over 1,000
buried drums containing TCE wastes from the
EDGY. Between 2003 and 2006, the EGDY pump-
and-treat system was updated by decommissioning
and replacing the original extraction wells and
reconfiguring the extraction well and reinjection
networks to optimize plume containment and
contaminant mass removal. The Army also
optimized the monitoring locations and sampling
frequency as needed, including the use of passive
diffusion bag samplers for the majority of monitoring
locations (U.S. Army, 2007). Between 2003 and
2007, in situ thermal treatment was performed in
three separate source areas at EGDY using ERH.
During each ERH application an array of electrodes
spaced about six meters apart heated the
subsurface both above and below the water table.
The ERH enhanced contaminant removal by
volatilizing chemicals and decreasing fluid viscosity, which allowed for extraction of LNAPL/DNAPL. Three
areas, totaling over 69,000 cubic yards of material, were treated up to 16 feet bgs, covering a total area of
approximately 1.5 acres. Liquid and vapor recovered from the subsurface was separated by phase and
treated with thermal oxidation. The ERH remediation system removed and treated an estimated 9,900
pounds of TCE, 2,000 pounds of c/s-1,2-dichoroethene (c/'s-1,2-DCE), and 114,400 pounds of petroleum
hydrocarbons (U.S. Army, 2007). Construction of the lower SLA pump-and-treat system began in 2007, was
completed in 2009, and continues along with the EGDY and Interstate 5 pump-and-treat systems. The SLA
pump-and-treat system is unique in that the discharge from the treatment tower is pumped to Madigan Army
Medical Center, where the water is used for cooling in the heating and ventilating system. A number of land
use controls (LUCs), including restricting the use of groundwater on-site and off-site, were also implemented
as components of the remedy and remain in place. The pump-and-treat system continues to operate with
quarterly long-term groundwater monitoring at the SLA system and semiannual long-term monitoring at the
EGDY and Interstate 5 systems.
In situ thermal treatment of DNAPL using electrical
resistive heating (ERH) at Fort Lewis Logistics
Center NPL Site (Thermal Remediation Services,
2008)
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Appendix B
Fort Lewis Logistics Center East Gate Disposal Yard (EGDY) OU1
Cleanup Success: Through targeted source area remedial actions (drum removal and in situ thermal
treatment) combined with optimized pump-and-treat systems, the Fort Lewis Logistics Center NPL site has
made significant progress towards meeting its cleanup levels. ERH treatment was successful at removing
significant contaminant mass and LNAPL/DNAPL from the source zones. The optimized pump-and-treat
systems have extracted and treated approximately 12,787 pounds of VOCs, and source area groundwater
TCE concentrations have been reduced to less than 210 |jg/L (ppb) from a maximum of 250,000 ppb priorto
the remedy (Knadle, 2011). As a result of the successful remediation program, Fort Lewis received the fiscal
year 2005 Secretary of Defense Environmental Award for Environmental Restoration.
Table 1. Groundwater TCE Concentration Reductions within ERH Treatment Areas
Cleanup Level
Pre-ERH Concentrations *
Post-ERH Concentration
TCE: 5 ppb
Maximum
Average
Maximum
Average
250,000 ppb
>1,000 ppb
210 ppb (2015**)
Not calculated,
exceeded MCL in
only one well
Sources: * U.S. Army, 2007; ** U.S. Army, 2016.
References
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Thermal Remediation Services, Inc.; In Situ Remediation Using Electrical Resistance Heating (ERH). Power
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Truex, Michael J., James M. Gillie, Jefferey G. Powers, and Kira P. Lynch. 2009. Assessment of In Situ
Thermal Treatment for Chlorinated Organic Source Zones. Wiley Periodicals, Inc. Published online in Wiley
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United States Department of Army; 2014 Annual Groundwater Monitoring Report. July, 2016.
United States Department of Army; 2015 Remedial Action Completion Report. Aug 2015b.
United States Department of Army; Third Five-Year Review Report for Fort Lewis CERCLA Sites: Pierce
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B-59
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